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ORGANIC SPECTROSCOPY

Read all about Organic Spectroscopy on ORGANIC SPECTROSCOPY INTERNATIONAL 

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DR ANTHONY MELVIN CRASTO Ph.D

DR ANTHONY MELVIN CRASTO Ph.D

DR ANTHONY MELVIN CRASTO, Born in Mumbai in 1964 and graduated from Mumbai University, Completed his Ph.D from ICT, 1991,Matunga, Mumbai, India, in Organic Chemistry, The thesis topic was Synthesis of Novel Pyrethroid Analogues, Currently he is working with GLENMARK PHARMACEUTICALS LTD, Research Centre as Principal Scientist, Process Research (bulk actives) at Mahape, Navi Mumbai, India. Total Industry exp 29 plus yrs, Prior to joining Glenmark, he has worked with major multinationals like Hoechst Marion Roussel, now Sanofi, Searle India Ltd, now RPG lifesciences, etc. He has worked with notable scientists like Dr K Nagarajan, Dr Ralph Stapel, Prof S Seshadri etc, He did custom synthesis for major multinationals in his career like BASF, Novartis, Sanofi, etc., He has worked in Discovery, Natural products, Bulk drugs, Generics, Intermediates, Fine chemicals, Neutraceuticals, GMP, Scaleups, etc, he is now helping millions, has 9 million plus hits on Google on all Organic chemistry websites. His friends call him worlddrugtracker. His New Drug Approvals, Green Chemistry International, All about drugs, Eurekamoments, Organic spectroscopy international, etc in organic chemistry are some most read blogs He has hands on experience in initiation and developing novel routes for drug molecules and implementation them on commercial scale over a 29 year tenure till date Aug 2016, Around 30 plus products in his career. He has good knowledge of IPM, GMP, Regulatory aspects, he has several International patents published worldwide . He has good proficiency in Technology transfer, Spectroscopy, Stereochemistry, Synthesis, Polymorphism etc., He suffered a paralytic stroke/ Acute Transverse mylitis in Dec 2007 and is 90 %Paralysed, He is bound to a wheelchair, this seems to have injected feul in him to help chemists all around the world, he is more active than before and is pushing boundaries, He has 9 million plus hits on Google, 2.5 lakh plus connections on all networking sites, 25 Lakh plus views on dozen plus blogs, He makes himself available to all, contact him on +91 9323115463, email amcrasto@gmail.com, Twitter, @amcrasto , He lives and will die for his family, 90% paralysis cannot kill his soul., Notably he has 13 lakh plus views on New Drug Approvals Blog in 212 countries......https://newdrugapprovals.wordpress.com/ , He appreciates the help he gets from one and all, Friends, Family, Glenmark, Readers, Wellwishers, Doctors, Drug authorities, His Contacts, Physiotherapist, etc

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Sreeni Labs Private Limited, Hyderabad, India ready to deliver New, Economical, Scalable Routes to your advanced intermediates & API’s in early Clinical Drug Development Stages


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Sreeni Labs Private Limited, Hyderabad, India is ready to take up challenging synthesis projects from your preclinical and clinical development and supply from few grams to multi-kilo quantities. Sreeni Labs has proven route scouting ability  to  design and develop innovative, cost effective, scalable routes by using readily available and inexpensive starting materials. The selected route will be further developed into a robust process and demonstrate on kilo gram scale and produce 100’s of kilos of in a relatively short time.

Accelerate your early development at competitive price by taking your route selection, process development and material supply challenges (gram scale to kilogram scale) to Sreeni Labs…………

INTRODUCTION

Sreeni Labs based in Hyderabad, India is working with various global customers and solving variety of challenging synthesis problems. Their customer base ranges from USA, Canada, India and Europe. Sreeni labs Managing Director, Dr. Sreenivasa Reddy Mundla has worked at Procter & Gamble Pharmaceuticals and Eli Lilly based in USA.

The main strength of Sreeni Labs is in the design, development of innovative and highly economical synthetic routes and development of a selected route into a robust process followed by production of quality product from 100 grams to 100s of kg scale. Sreeni Labs main motto is adding value in everything they do.

They have helped number of customers from virtual biotech, big pharma, specialty chemicals, catalog companies, and academic researchers and drug developers, solar energy researchers at universities and institutions by successfully developing highly economical and simple chemistry routes to number of products that were made either by very lengthy synthetic routes or  by using highly dangerous reagents and Suzuki coupling steps. They are able to supply materials from gram scale to multi kilo scale in a relatively short time by developing very short and efficient synthetic routes to a number of advanced intermediates, specialty chemicals, APIs and reference compounds. They also helped customers by drastically reducing number of steps, telescoping few steps into a single pot. For some projects, Sreeni Labs was able to develop simple chemistry and avoided use of palladium & expensive ligands. They always begin the project with end in the mind and design simple chemistry and also use readily available or easy to prepare starting materials in their design of synthetic routes

Over the years, Sreeni labs has successfully made a variety of products ranging from few mg to several kilogram scale. Sreeni labs has plenty of experience in making small select libraries of compounds, carbocyclic compounds like complex terpenoids, retinal derivatives, alkaloids, and heterocyclic compounds like multi substituted beta carbolines, pyridines, quinolines, quinolones, imidazoles, aminoimidazoles, quinoxalines, indoles, benzimidazoles, thiazoles, oxazoles, isoxazoles, carbazoles, benzothiazoles, azapines, benzazpines, natural and unnatural aminoacids, tetrapeptides, substituted oligomers of thiophenes and fused thiophenes, RAFT reagents, isocyanates, variety of ligands,  heteroaryl, biaryl, triaryl compounds, process impurities and metabolites.

Sreeni Labs is Looking for any potential opportunities where people need development of cost effective scalable routes followed by quick scale up to produce quality products in the pharmaceutical & specialty chemicals area. They can also take up custom synthesis and scale up of medchem analogues and building blocks.  They have flexible business model that will be in sink with customers. One can test their abilities & capabilities by giving couple of PO based (fee for service) projects.

Some of the compounds prepared by Sreeni labs;

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See presentation below

LINK ON SLIDESHARE

Sreeni Labs Profile from Sreenivasa Reddy

Managing Director at Sreeni Labs Private Limited\

 

Few Case Studies : Source SEEENI LABS

QUOTE………….

One virtual biotech company customer from USA, through a common friend approached Sreeni Labs and told that they are buying a tetrapeptide from Bachem on mg scale at a very high price and requested us to see if we can make 5g. We accepted the challenge and developed solution phase chemistry and delivered 6g and also the process procedures in 10 weeks time. The customer told that they are using same procedures with very minor modifications and produced the tetrapeptide ip to 100kg scale as the molecule is in Phase III.

 

One East coast customer in our first meeting told that they are working with 4 CROs of which two are in India and two are in China and politely asked why they should work with Sreeni Labs. We told that give us a project where your CROs failed to deliver and we will give a quote and work on it. You pay us only if we deliver and you satisfy with the data. They immediately gave us a project to make 1.5g and we delivered 2g product in 9 weeks. After receiving product and the data, the customer was extremely happy as their previous CRO couldn’t deliver even a milligram in four months with 3 FTEs.

 

One Midwest biotech company was struggling to remove palladium from final API as they were doing a Suzuki coupling with a very expensive aryl pinacol borane and bromo pyridine derivative with an expensive ligand and relatively large amount of palldium acetate. The cost of final step catalyst, ligand and the palladium scavenging resin were making the project not viable even though the product is generating excellent data in the clinic. At this point we signed an FTE agreement with them and in four months time, we were able to design and develop a non suzuki route based on acid base chemistry and made 15g of API and compared the analytical data and purity with the Suzuki route API. This solved all three problems and the customer was very pleased with the outcome.

 

One big pharma customer from east coast, wrote a structure of chemical intermediate on a paper napkin in our first meeting and asked us to see if we can make it. We told that we can make it and in less than 3 weeks time we made a gram sample and shared the analytical data. The customer was very pleased and asked us to make 500g. We delivered in 4 weeks and in the next three months we supplied 25kg of the same product.

 

Through a common friend reference, a European customer from a an academic institute, sent us an email requesting us to quote for 20mg of a compound with compound number mentioned in J. med. chem. paper. It is a polycyclic compound with four contiguous stereogenic centers.  We gave a quote and delivered 35 mg of product with full analytical data which was more pure than the published in literature. Later on we made 8g and 6g of the same product.

 

One West coast customer approached us through a common friend’s reference and told that they need to improve the chemistry of an advanced intermediate for their next campaign. At that time they are planning to make 15kg of that intermediate and purchased 50kg of starting raw material for $250,000. They also put five FTEs at a CRO  for 5 months to optimize the remaining 5 steps wherein they are using LAH, Sodium azide,  palladium catalyst and a column chromatography. We requested the customer not to purchase the 50kg raw material, and offered that we will make the 15kg for the price of raw material through a new route  in less than three months time. You pay us only after we deliver 15 kg material. The customer didn’t want to take a chance with their timeline as they didn’t work with us before but requested us to develop the chemistry. In 7 weeks time, we developed a very simple four step route for their advanced intermediate and made 50g. We used very inexpensive and readily available starting material. Our route gave three solid intermediates and completely eliminated chromatographic purifications.

 

One of my former colleague introduced an academic group in midwest and brought us a medchem project requiring synthesis of 65 challenging polyene compounds on 100mg scale. We designed synthetic routes and successfully prepared 60 compounds in a 15 month time.  

UNQUOTE…………

 

The man behind Seeni labs is Dr. Sreenivasa Reddy Mundla 

Sreenivasa Reddy

Dr. Sreenivasa Reddy Mundla.

Managing Director at Sreeni Labs Private Limited

Sreeni Labs Private Limited

Road No:12, Plot No:24,25,26

  • IDA, Nacharam
    Hyderabad, 500076
    Telangana State, India

Links

LINKEDIN https://in.linkedin.com/in/sreenivasa-reddy-10b5876

FACEBOOK https://www.facebook.com/sreenivasa.mundla

RESEARCHGATE https://www.researchgate.net/profile/Sreenivasa_Mundla/info

EMAIL mundlasr@hotmail.com,  Info@sreenilabs.com, Sreeni@sreenilabs.com

Dr. Sreenivasa  Reddy Mundla

Dr. M. Sreenivasa Reddy obtained Ph.D from University of Hyderabad under the direction Prof Professor Goverdhan Mehta in 1992. From 1992-1994, he was a post doctoral fellow at University of Wisconsin in Professor Jame Cook’s lab. From 1994 to 2000,  worked at Chemical process R&D at Procter & Gamble Pharmaceuticals (P&G). From 2001 to 2007 worked at Global Chemical Process R&D at Eli Lilly and Company in Indianapolis. 

In 2007  resigned to his  job and founded Sreeni Labs based in Hyderabad, Telangana, India  and started working with various global customers and solving various challenging synthesis problems. 
The main strength of Sreeni Labs is in the design, development of a novel chemical route and its development into a robust process followed by production of quality product from 100 grams to 100’s of kg scale.
 

They have helped number of customers by successfully developing highly economical simple chemistry routes to number of products that were made by Suzuki coupling. they are able to shorten the route by drastically reducing number of steps, avoiding use of palladium & expensive ligands. they always use readily available or easy to prepare starting materials in their design of synthetic routes.

Sreeni Labs is Looking for any potential opportunities where people need development of cost effective scalable routes followed by quick scale up to produce quality products in the pharmaceutical & specialty chemicals area. They have flexible business model that will be in sink with customers. One can test their abilities & capabilities by giving PO based projects

Experience

Founder & Managing Director

Sreeni Labs Private Limited

August 2007 – Present (8 years 11 months)

Sreeni Labs Profile

Sreeni Labs Profile

View On SlideShare

Principal Research Scientist

Eli Lilly and Company

March 2001 – August 2007 (6 years 6 months)

Senior Research Scientist

Procter & Gamble

July 1994 – February 2001 (6 years 8 months)

Education

University of Hyderabad

Doctor of Philosophy (Ph.D.), 
1986 – 1992

 

PUBLICATIONS

Article: Expansion of First-in-Class Drug Candidates That Sequester Toxic All-Trans-Retinal and Prevent Light-Induced Retinal Degeneration

Jianye Zhang · Zhiqian Dong · Sreenivasa Reddy Mundla · X Eric Hu · William Seibel ·Ruben Papoian · Krzysztof Palczewski · Marcin Golczak

Article: ChemInform Abstract: Regioselective Synthesis of 4Halo ortho-Dinitrobenzene Derivative

Sreenivasa Mundla

Aug 2010 · ChemInform

Article: Optimization of a Dihydropyrrolopyrazole Series of Transforming Growth Factor-β Type I Receptor Kinase Domain Inhibitors: Discovery of an Orally Bioavailable Transforming Growth Factor-β Receptor Type I Inhibitor as Antitumor Agent

Hong-yu Li · William T. McMillen · Charles R. Heap · Denis J. McCann · Lei Yan · Robert M. Campbell · Sreenivasa R. Mundla · Chi-Hsin R. King · Elizabeth A. Dierks · Bryan D. Anderson · Karen S. Britt · Karen L. Huss

Apr 2008 · Journal of Medicinal Chemistry

Article: ChemInform Abstract: A Concise Synthesis of Quinazolinone TGF-β RI Inhibitor Through One-Pot Three-Component Suzuki—Miyaura/Etherification and Imidate—Amide Rearrangement Reactions

Hong-yu Li · Yan Wang · William T. McMillen · Arindam Chatterjee · John E. Toth ·Sreenivasa R. Mundla · Matthew Voss · Robert D. Boyer · J. Scott Sawyer

Feb 2008 · ChemInform

Article: ChemInform Abstract: A Concise Synthesis of Quinazolinone TGF-β RI Inhibitor Through One-Pot Three-Component Suzuki—Miyaura/Etherification and Imidate—Amide Rearrangement Reactions

Hong-yu Li · Yan Wang · William T. McMillen · Arindam Chatterjee · John E. Toth ·Sreenivasa R. Mundla · Matthew Voss · Robert D. Boyer · J. Scott Sawyer

Nov 2007 · Tetrahedron

Article: Dihydropyrrolopyrazole Transforming Growth Factor-β Type I Receptor Kinase Domain Inhibitors: A Novel Benzimidazole Series with Selectivity versus Transforming Growth Factor-β Type II Receptor Kinase and Mixed Lineage Kinase-7

Hong-yu Li · Yan Wang · Charles R Heap · Chi-Hsin R King · Sreenivasa R Mundla · Matthew Voss · David K Clawson · Lei Yan · Robert M Campbell · Bryan D Anderson · Jill R Wagner ·Karen Britt · Ku X Lu · William T McMillen · Jonathan M Yingling

Apr 2006 · Journal of Medicinal Chemistry

Read full-textSource

Article: Studies on the Rh and Ir mediated tandem Pauson–Khand reaction. A new entry into the dicyclopenta[ a, d]cyclooctene ring system

Hui Cao · Sreenivasa R. Mundla · James M. Cook

Aug 2003 · Tetrahedron Letters

Article: ChemInform Abstract: A New Method for the Synthesis of 2,6-Dinitro and 2Halo6-nitrostyrenes

Sreenivasa R. Mundla

Nov 2000 · ChemInform

Article: ChemInform Abstract: A Novel Method for the Efficient Synthesis of 2-Arylamino-2-imidazolines

Read at

[LINK]

Patents by Inventor Dr.Sreenivasa Reddy Mundla

  • Patent number: 7872020

    Abstract: The present invention provides crystalline 2-(6-methyl-pyridin-2-yl)-3-[6-amido-quinolin-4-yl)-5,6-dihydro -4H-pyrrolo[1,2-b]pyrazole monohydrate.

    Type: Grant

    Filed: June 29, 2006

    Date of Patent: January 18, 2011

    Assignee: Eli Lilly and Company

    Inventor: Sreenivasa Reddy Mundla

  • Publication number: 20100120854

    Abstract: The present invention provides crystalline 2-(6-methyl-pyridin-2-yl)-3-[6-amido-quinolin-4-yl)-5,6-dihydro-4H-pyrrolo[1,2-b]pyrazole monohydrate.

    Type: Application

    Filed: June 29, 2006

    Publication date: May 13, 2010

    Applicant: ELI LILLY AND COMPANY

    Inventor: Sreenivasa Reddy Mundla

  • Patent number: 6066740

    Abstract: The present invention provides a process for making 2-amino-2-imidazoline, guanidine, and 2-amino-3,4,5,6-tetrahydroyrimidine derivatives by preparing the corresponding activated 2-thio-subsituted-2-derivative in a two-step, one-pot procedure and by further reacting yields this isolated derivative with the appropriate amine or its salts in the presence of a proton source. The present process allows for the preparation of 2-amino-2-imidazolines, quanidines, and 2-amino-3,4,5,6-tetrahydropyrimidines under reaction conditions that eliminate the need for lengthy, costly, or multiple low yielding steps, and highly toxic reactants. This process allows for improved yields and product purity and provides additional synthetic flexibility.

    Type: Grant

    Filed: November 25, 1997

    Date of Patent: May 23, 2000

    Assignee: The Procter & Gamble Company

    Inventors: Michael Selden Godlewski, Sean Rees Klopfenstein, Sreenivasa Reddy Mundla, William Lee Seibel, Randy Stuart Muth

TGF-β inhibitors

US 7872020 B2

Sreenivasa Reddy Mundla

The present invention provides 2-(6-methyl-pyridin-2-yl)-3-[6-amido-quinolin-4-yl) -5,6-dihydro-4H-pyrrolo[1,2-b]pyrazole monohydrate, i.e., Formula I.

Figure US07872020-20110118-C00002

EXAMPLE 1 Preparation of 2-(6-methyl-pyridin-2-yl)-3-[6-amido-quinolin-4-yl-5,6-dihydro-4H -pyrrolo[1,2-b]pyrazole monohydrate

Figure US07872020-20110118-C00008

Galunisertib

1H NMR (CDCl3): δ=9.0 ppm (d, 4.4 Hz, 1H); 8.23-8.19 ppm (m, 2H); 8.315 ppm (dd, 1.9 Hz, 8.9 Hz, 1H); 7.455 ppm (d, 4.4 Hz, 1H); 7.364 ppm (t, 7.7 Hz, 1H); 7.086 ppm (d, 8.0 Hz, 1H); 6.969 ppm (d, 7.7 Hz, 1H); 6.022 ppm (m, 1H); 5.497 ppm (m, 1H); 4.419 ppm (t, 7.3 Hz, 2H); 2.999 ppm (m, 2H); 2.770 ppm (p, 7.2 Hz, 7.4 Hz, 2H); 2.306 ppm (s, 3H); 1.817 ppm (m, 2H). MS ES+: 370.2; Exact: 369.16

ABOVE MOLECULE IS

https://newdrugapprovals.org/2016/05/04/galunisertib/

Galunisertib

Phase III

LY-2157299

CAS No.700874-72-2

 

 

READ MY PRESENTATION ON

Accelerating Generic Approvals, see how you can accelerate your drug development programme

Accelerating Generic Approvals by Dr Anthony Crasto

KEYWORDS   Sreenivasa Mundla Reddy, Managing Director, Sreeni Labs Private Limited, Hyderabad, Telangana, India,  new, economical, scalable routes, early clinical drug development stages, Custom synthesis, custom manufacturing, drug discovery, PHASE 1, PHASE 2, PHASE 3,  API, drugs, medicines

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Chemistry in Water


Chemistry in Water


1
Isley et al. reported the use of the nonionic amphiphile TPGS-750-M (2 wt %) in water to facilitate nucleophilic aromatic substitution reactions (SNAr) with oxygen, nitrogen, and sulfur nucleophiles. The team eliminated the use of dipolar aprotic organic solvents traditionally required for SNAr reactions, such as dimethylformamide (DMF), dimethylacetamide (DMAc), dimethyl sulfoxide (DMSO), and N-methyl-2-pyrrolidone (NMP).
Moderate to high yields at ambient or slightly elevated temperatures (up to 45 °C) were observed, and a diverse substrate scope with respect to thermal stability was established. The team additionally demonstrated the ability to recycle the water/micelle mixture by extracting the product with organic solvent. Recycling of the aqueous media resulted in improving the E-factor and reducing aqueous waste ( Org. Lett. 2015, 17,4734−4737).Supporting Info

Nucleophilic Aromatic Substitution Reactions in Water Enabled by Micellar Catalysis

Department of Chemistry & Biochemistry, University of California, Santa Barbara, California 93106, United States
Chemical & Analytical Development, Novartis Pharma AG, 4056 Basel, Switzerland
Org. Lett., 2015, 17 (19), pp 4734–4737
DOI: 10.1021/acs.orglett.5b02240
STR1
2
Wang et al. described the development of a copper-catalyzed hydroxylation of aryl halides in water. The syntheses of phenols generally require the use of energy intensive and/or harsh reaction conditions which can impact the substrate scope. This methodology utilized a hydroxylated phenanthroline ligand to improve solubility in water. Optimization of this method through screening resulted in the selection of copper(I) oxide (Cu2O) as the copper source and tetrabutyl-ammonium hydroxide (TBAOH) at 110 °C. The TBAOH was proposed to function as both phase transfer catalyst and nucleophile, resulting in high yields and excellent selectivity toward phenol versus biphenyl ether.
The scope of this method with substituted aryl halides was demonstrated, affording excellent yields and high selectivity for para-substituted electron-rich and electron-deficient aryl bromides, as well as meta-substituted bromo-halides. Functional groups such as carboxyl and hydroxyl groups were also tolerated. The team additionally demonstrated a one-pot synthesis of either alkyl aryl ethers or benzofuran by trapping the in situ generated phenol with an alkyl bromide or through intramolecular cyclization ( Green Chem. 2015, 17, 3910−3915).
Graphical abstract: Copper-catalyzed hydroxylation of aryl halides: efficient synthesis of phenols, alkyl aryl ethers and benzofuran derivatives in neat water
Yangxin Wang,ab   Chunshan Zhoua and   Ruihu Wang*a  
*Corresponding authors
aState Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, China
E-mail: ruihu@fjirsm.ac.cn
bUniversity of Chinese Academy of Sciences, Beijing, China
Green Chem., 2015, 17, 3910-3915
DOI: 10.1039/C5GC00871A , supporting info,
 An efficient catalytic protocol for hydroxylation of aryl halides in water is proposed to prepare phenols, ethers and benzofuran derivatives.
A thorough study of environmentally friendly hydroxylation of aryl halides is presented. The best protocol consists of hydroxylation of different aryl bromides and electron-deficient aryl chlorides by water solution of tetrabutylammonium hydroxide catalyzed by Cu2O/4,7-dihydroxy-1,10-phenanthroline. Various phenol derivatives can be obtained in excellent selectivity and great functional group tolerance. This methodology also provides a direct pathway for the formation of alkyl aryl ethers and benzofuran derivatives in a one-pot tandem reaction.
3
Jung et al. reported the use of a continuous flow reactor to synthesize propargylamines in an atom economic fashion using stoichiometric quantities of reagents, water as solvent, and generating only CO2 and water as byproducts. The team exploited the use of a pressurized tube reactor to achieve temperatures above the boiling point of water, enabling excellent yields (≥88%) and reasonable residence time (2 h).
This procedure improved the atom economy of previously reported methods for this transformation by eliminating the use of transition metal catalysts and excess of reagents. The substrate scope was demonstrated for multiple alkynyl carboxylic acids and secondary amines ( Tetrahedron. Lett. 2015, 56, 4697−4700).
image

Volume 52, Issue 36, 7 September 2011, Pages 4697–4700

Basic alumina supported tandem synthesis of bridged polycyclic quinolino/isoquinolinooxazocines under microwave irradiation

  • Department of Chemistry, Indian Institute of Chemical Biology, Council of Scientific and Industrial Research, 4 Raja S.C. Mullick Road, Jadavpur, Kolkata 700 032, India
4
Wang et al. reported the synthesis of an easily accessible diammonium functionalized Ru-alkylidene complex capable of ring-closing metathesis (RCM) and cross metathesis (CM) reactions in water. The NHBoc penultimate intermediate was isolated as an air-stable, nonhygroscopic Ru-alkylidene complex. Acidic cleavage of the Boc groups with trifluoroacetic acid (TFA) in dichloromethane generated the diammonium catalyst as a green solid after removal of volatiles under reduced pressure. The diammonium catalyst (5 mol %) achieved modest to high conversion to cyclic RCM products in D2O at ambient to elevated temperatures (up to 80 °C). Lowering the catalyst loading to 0.1 mol % established a turnover number (TON) of >900.
Homocoupling of allyl alcohol and long chain alkenylammonium salts provided the desired diammonium cross products in high yield/conversion. Short chain alkenyl-ammonium salts were poor substrates for the CM reaction.
Catalyst deactivation was attributed to the ammonium:free amine equilibration in water followed by Lewis basic nitrogen coordination to the Ru-center (Green Chem. 2015, 17, 3407−3414).
Graphical abstract: A simple and practical preparation of an efficient water soluble olefin metathesis catalyst

A simple and practical preparation of an efficient water soluble olefin metathesis catalyst

*Corresponding authors
aSchool of Chemistry, Monash University, Clayton 3800, Australia
E-mail: andrea.robinson@monash.edu
Green Chem., 2015,17, 3407-3414

DOI: 10.1039/C5GC00252D, supp info

5
The same research group additionally reported the divergent functionalization of L-tyrosine to generate a family of tyrosine-derived Ru-alkylidene RCM catalysts. This common ligand precursor approach was utilized to successfully create not only a hydrophilic/water-soluble PEG Ru-alkylidene, but a hydrophobic alkane Ru-alkylidene for solvent-free catalysis and a solid-phase supported Ru-alkylidene to access a potentially recyclable precatalyst system.
The PEG Ru-alkylidene complex displayed poor solubility in water at 40 °C under ultrasonication, providing the desired model RCM product in only 25% conversion. >95% conversion was achieved by utilizing a 1:1 water–MeOH solvent system at 40 °C with 2.5 mol % catalyst loading. It was rationalized in the Green Chemistry report (vide supra) that functionalization of the benzylidene ligand to increase aqueous solubility may be problematic due to the dissociation of the labile ligand during the catalytic cycle, whereas functionalization of nondissociating NHC ligand could sustain the desired solubility throughout the reaction.
The hydrophobic alkane Ru-alkylidene provided solvent-free RCM and CM products in high conversion. The solid-phase Ru-alkylidene also provided the desired RCM products in high conversion and demonstrated stable performance after multiple catalyst recovery/reuse operations. Sustained leaching of Ru metal into the reaction media was monitored and observed for the recycled solid-phase catalyst method. However, this iterative loss of metal did not negatively impact conversion ( J. Org. Chem. 2015, 80, 7205−7211).

Divergent Approach to a Family of Tyrosine-Derived Ru−Alkylidene Olefin Metathesis Catalysts

divergent

Authors

Ellen C. Gleeson, Zhen J. Wang, W. Roy Jackson, and Andrea J. Robinson

Published Journal of Organic Chemistry
Graphical abstract divergent
Abstract

A simple and generic approach to access a new family of Ru−alkylidene olefin metathesis catalysts with specialized properties is reported. This strategy utilizes a late stage, utilitarian Hoveyda-type ligand derived from tyrosine, which can be accessed via a multigram-scale synthesis. Further functionalization allows the catalyst properties to be tuned, giving access to modified second-generation Hoveyda−Grubbs-type catalysts. This divergent synthetic approach can be used to access solid-supported catalysts and catalysts that function under solvent-free and aqueous conditions.

Citation

Ellen C. Gleeson, Zhen J. Wang, W. Roy Jackson, and Andrea J. Robinson, J. Org. Chem., 201580(14), 7205–7211

Pdf Article
Doi 10.1021/acs.joc.5b01091
6
Bhowmick et al. published a review “Water: the most versatile and nature’s friendly media in asymmetric organocatalyzed direct aldol reactions”. This review addressed the various types of organocatalysts based on (1) l-proline, (2) 4-hydroxy-l-proline, (3) amino acid derivatives, (4) enzymes, and (5) other miscellaneous catalysts applied to the aldol reaction in aqueous media. In general, the intermolecular asymmetric aldol reaction has been shown to perform poorly in pure aqueous media and is typically performed in organic solvents such as DMF, DMSO, etc.
However, structural modifications to l-proline and 4-hydroxy-l-proline have generated catalysts capable of asymmetric aldol reactions in aqueous media.
Examples provided in this review highlight (a) instances of enhanced reactivity using water as a solvent, cosolvent, or additive, (b) formation of enzyme mimics that use hydrophobic forces to reinforce substrate/catalyst binding, (c) the use of aqueous media to interrogate proposed transition state geometries, and (d) the pH dependence of organocatalyzed aldol reactions. Limitations presented in the review include (a) substrate specific catalyst activities, (b) multistep/low-yielding synthesis of the organocatalysts, (c) slow catalysis rate in pure aqueous media, (d) high catalyst loading, and (e) poor to moderate selectivity (Tetrahedron: Asymmetry 2015, 26, 1215−1244).
Image for unlabelled figure

Volume 26, Issues 21–22, 1 December 2015, Pages 1215–1244

Tetrahedron: Asymmetry Report Number 159

Water: the most versatile and nature’s friendly media in asymmetric organocatalyzed direct aldol reactions

  • Division of Organic Synthesis, Department of Chemistry, Visva-Bharati (A Central University), Bolpur, West Bengal 731 235, India
7
Hot water’s ability to promote unexpected reactions without any other reagents or catalysts.

Chinese and Japanese chemists have highlighted hot water’s ability to promote unexpected reactions without any other reagents or catalysts. The work should expand our understanding of how to harness the physicochemical properties of water to potentially replace more complex reagents and catalysts.

Above its critical point at 374°C and 218atm the properties of water change quite dramatically, explains Hiizu Iwamura from Nihon University in Tokyo. But even below that point, as water is heated, hydrogen bonding and hydrophobic interactions are disrupted. ‘This means that organic compounds get more soluble and salts become insoluble in hot pressurised water,’ Iwamura says. Dissociation of water into hydroxide (OH) and hydronium (H3O+) ions also increases, he adds, so there are higher concentrations of these ions available to act as catalysts for reactions.

Iwamura was synthesising triaroylbenzene molecules for a previous project on molecular magnets, using base-catalysed Michael addition reactions, when he first became interested in whether the reactions might work in water. He teamed up with a chemical engineer colleague, Toshihiko Hiaki, who is more familiar with working at the required temperatures and pressures. Together, they found that 4-methoxy-3-buten-2-one could be transformed into 1,3,5-triacetylbenzene in pressurised water at 150°C, with no other additives (see reaction scheme).1

Meanwhile, Jin Qu and her team at Nankai University in Tianjin have been investigating water-promoted reactions at lower temperatures, without the need for pressurised vessels, which Qu says is more accessible for many researchers and makes monitoring reactions easier. ‘In 2008, one of my students found he could hydrolyse epoxides in pure water at 60°C, in 90% yields,’ she explains. ‘At first I thought it was not very interesting, just a hydrogen-bonding effect, but as we found more examples I got more interested.’

More than a thermal effect

When Qu’s team hydrolysed an epoxide made from (-)-α-pinene, they found that at room temperature they got (-)-sobrerol, the product they expected. But at 60°C or higher, the sobrerol began to racemise, giving a mixture of the (+)- and (-)-forms (see reaction scheme). ‘We couldn’t understand why this was happening at first,’ says Qu, but eventually it became clear that the allylic alcohol group in the sobrerol, which is much less reactive than the epoxide in pinene, was also being hydrolysed. The same reactions happen at room temperature if acid is added, Qu says, but don’t happen in propanol or other alcoholic and hydrogen-bonding solvents heated to the same temperatures, so it is not simply a thermal effect.

Qu points out that these observations, along with those of Iwamura’s team, show that molecules that might usually be considered unreactive in water can undergo useful transformations. And these reactions can take place without other reagents or solvents, which would create extra waste streams. Also, owing to the decreased solubility of the organic product molecules when the solutions are cooled back to room temperature, they are often easy to purify as well.

Iwamura suggests that there are many other simple acid- and base-catalysed reactions that might be suitable for reacting in hot water. However, reactions with thermally unstable molecules, or those requiring delicate selectivity, are unlikely to be so effective at higher temperatures, he adds. He also makes a distinction between Qu’s work – in which the water molecules are directly involved in the reaction – and his own group’s, in which the water acts as the reaction medium and provides the catalyst. ‘Our reaction did not take place in water heated at reflux,’ Iwamura adds.

However, Hiaki points out that the potential environmental benefits of reduced waste streams will have little impact on industrial chemistry if the reactions remain confined to batch processes. ‘High temperature and pressure is detrimental for the scale up to commercial chemical plants,’ he says. For that reason, the team is developing a flow microreactor system that should be more industry compatible.REFERENCES, 1 T Iwado et al, J. Org. Chem., 2012, DOI: 10.1021/jo301979pZ-B Xu and J Qu, Chem. Eur. J., 2012 DOI: 10.1002/chem.201202886

 8
Hydration: A process which adds water.

In this hydration reaction, 1-methylcyclohexene (an alkene) is reacted with aqueous H3O+ (formed from water and a strong acid such as H2SO4), resulting in Markovnikov addition of water across the pi bond. The product is an alcohol.


Syn, anti-Markovnikov addition of water to an alkene can be achieved via a hydroboration-oxidation reaction.

–to be added– –to be added–
CuSO4 (anhydrous) CuSO4 . 5 H2O

Anhydrous CuSO4 (colorless) absorbs water vapor from the air, hydrating it to CuSO4 . 5 H2O (copper sulfate pentahydrate; blue).

///////////Chemistry in Water

Palladium-Catalyzed Suzuki Reactions in Water with No Added Ligand: Effects of Reaction Scale, Temperature, pH of Aqueous Phase, and Substrate Structure


Abstract Image

The heterogeneous palladium-catalyzed Suzuki reactions between model aryl bromides (4-bromoanisole, 4-bromoaniline, 4-amino-2-bromopyridine, and 2-bromopyridine) and phenylboronic acid have been successfully conducted in water with no added ligand at the 100 mL scale using 20–40 mmol of aryl bromide. The product yields associated with these substrates were optimized, and key reaction parameters affecting the yields were identified. The results clearly indicate that the reaction parameters necessary to achieve high yields are substrate-dependent. In addition, it is demonstrated that aqueous Suzuki reactions of substrates containing basic nitrogen centers can produce quantitative yields of desired products in the absence of added ligand.

Palladium-Catalyzed Suzuki Reactions in Water with No Added Ligand: Effects of Reaction Scale, Temperature, pH of Aqueous Phase, and Substrate Structure

School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
§ The Dow Chemical Company, Midland, Michigan 48674, United States
Org. Process Res. Dev., Article ASAP
DOI: 10.1021/acs.oprd.6b00180

http://pubs.acs.org/doi/abs/10.1021/acs.oprd.6b00180

//////////

Review, Continuous Processing


Continuous Processing

Continuous production is a flow production method used to manufacture, produce, or process materials without interruption. Continuous production is called a continuous process or a continuous flow process because the materials, either dry bulk or fluids that are being processed are continuously in motion, undergoing chemical reactions or subject to mechanical or heat treatment. Continuous processing is contrasted with batch production.

Continuous usually means operating 24 hours per day, seven days per week with infrequent maintenance shutdowns, such as semi-annual or annual. Some chemical plants can operate for more than one or two years without a shutdown. Blast furnaces can run four to ten years without stopping.[1]

Production workers in continuous production commonly work in rotating shifts.

Processes are operated continuously for practical as well as economic reasons. Most of these industries are very capital intensive and the management is therefore very concerned about lost operating time.

Shutting down and starting up many continuous processes typically results in off quality product that must be reprocessed or disposed of. Many tanks, vessels and pipes cannot be left full of materials because of unwanted chemical reactions, settling of suspended materials or crystallization or hardening of materials. Also, cycling temperatures and pressures from starting up and shutting down certain processes (line kilns, boilers, blast furnaces, pressure vessels, etc.) may cause metal fatigue or other wear from pressure or thermal cycling.

In the more complex operations there are sequential shut down and start up procedures that must be carefully followed in order to protect personnel and equipment. Typically a start up or shut down will take several hours.

Continuous processes use process control to automate and control operational variables such as flow rates, tank levels, pressures, temperatures and machine speeds.[2]

Semi-continuous processes

Many processes such as assembly lines and light manufacturing that can be easily shut down and restarted are today considered semi-continuous. These can be operated for one or two shifts if necessary.

History

The oldest continuous flow processes is the blast furnace for producing pig iron. The blast furnace is intermittently charged with ore, fuel and flux and intermittently tapped for molten pig iron and slag; however, the chemical reaction of reducing the iron and silicon and later oxidizing the silicon is continuous.

Semi-continuous processes, such as machine manufacturing of cigarettes, were called “continuous” when they appeared.

Many truly continuous processes of today were originally batch operations.

The Fourdrinier paper machine, patented in 1799, was one of the earliest of the industrial revolution era continuous manufacturing processes. It produced a continuous web of paper that was formed, pressed, dried and reeled up in a roll. Previously paper had been made in individual sheets.

Another early continuous processes was Oliver Evans‘es flour mill (ca. 1785), which was fully automated.

Early chemical production and oil refining was done in batches until process control was sufficiently developed to allow remote control and automation for continuous processing. Processes began to operate continuously during the 19th century. By the early 20th century continuous processes were common.

Shut-downs

In addition to performing maintenance, shut downs are also when process modifications are performed. These include installing new equipment in the main process flow or tying-in or making provisions to tie-in sub-processes or equipment that can be installed while the process is operating.

Shut-downs of complicated processes may take weeks or months of planning. Typically a series of meetings takes place for co-ordination and planning. These typically involve the various departments such as maintenance, power, engineering, safety and operating units.

All work is done according to a carefully sequenced schedule that incorporates the various trades involved, such as pipe-fitters, millwrights, mechanics, laborers, etc., and the necessary equipment (cranes, mobile equipment, air compressors, welding machines, scaffolding, etc.) and all supplies (spare parts, steel, pipe, wiring, nuts and bolts) and provisions for power in case power will also be off as part of the outage. Often one or more outside contractors perform some of the work, especially if new equipment is installed.

Safety

Safety meetings are typically held before and during shutdowns. Other safety measures include providing adequate ventilation to hot areas or areas where oxygen may become depleted or toxic gases may be present and checking vessels and other enclosed areas for adequate levels of oxygen and insure absence of toxic or explosive gases. Any machines that are going to be worked on must be electrically disconnected, usually through the motor starter, so that it cannot operate. It is common practice to put a padlock on the motor starter, which can only be unlocked by the person or persons who is or are endangered by performing the work. Other disconnect means include removing couplings between the motor and the equipment or by using mechanical means to keep the equipment from moving. Valves on pipes connected to vessels that workers will enter are chained and locked closed, unless some other means is taken to insure that nothing will come through the pipes.

Continuous processor (equipment)

Continuous Production can be supplemented using a Continuous Processor. Continuous Processors are designed to mix viscous products on a continuous basis by utilizing a combination of mixing and conveying action. The Paddles within the mixing chamber (barrel) are mounted on two co-rotating shafts that are responsible for mixing the material. The barrels and paddles are contoured in such a way that the paddles create a self-wiping action between themselves minimizing buildup of product except for the normal operating clearances of the moving parts. Barrels may also be heated or cooled to optimize the mixing cycle. Unlike an extruder, the Continuous Processor void volume mixing area is consistent the entire length of the barrel ensuring better mixing and little to no pressure build up. The Continuous Processor works by metering powders, granules, liquids, etc. into the mixing chamber of the machine. Several variables allow the Continuous Processor to be versatile for a wide variety of mixing operations:[3]

  1. Barrel Temperature
  2. Agitator speed
  3. Fed rate, accuracy of feed
  4. Retention time (function of feed rate and volume of product within mixing chamber)

Continuous Processors are used in the following processes:

  • Compounding
  • Mixing
  • Kneading
  • Shearing
  • Crystallizing
  • Encapsulating

The Continuous Processor has an unlimited material mixing capabilities but, it has proven its ability to mix:

  • Plastics
  • Adhesives
  • Pigments
  • Composites
  • Candy
  • Gum
  • Paste
  • Toners
  • Peanut Butter
  • Waste Products

EXAMPLE…………….

Abstract Image

In the development of a new route to bendamustine hydrochloride, the API in Treanda, the key benzimidazole intermediate 5 was generated via catalytic heterogeneous hydrogenation of an aromatic nitro compound using a batch reactor. Because of safety concerns and a site limitation on hydrogenation at scale, a continuous flow hydrogenation for the reaction was investigated at lab scale using the commercially available H-Cube. The process was then scaled successfully, generating kilogram quantities on the H-Cube Midi. This flow process eliminated the safety concerns about the use of hydrogen gas and pyrophoric catalysts and also showed 1200-fold increase in space–time yield versus the batch processing.

Improved Continuous Flow Processing: Benzimidazole Ring Formation via Catalytic Hydrogenation of an Aromatic Nitro Compound

Org. Process Res. Dev., 2014, 18 (11), pp 1427–1433
Figure

EXAMPLE…………….


Correia et al. have published a three-step flow synthesis of rac-Effavirenz. This short synthetic route begins with cryogenic trifluoroacetylation of 1,4-dichlorobenzene. After quench and removal of morpholine using silica gel, this intermediate could either be isolated, or the product stream could be used directly in the next alkynylation step. Nucleophilic addition of lithium cyclopropylacetylide to the trifluoroacetate gave the propargyl alcohol intermediate in 90% yield in under 2 min residence time. This reaction was temperature-sensitive, and low temperatures were required to minimize decomposition. Again silica gel proved effective in the quench of the reaction. However, residual alkyne and other byproducts were difficult to remove. Thus, isolation of this intermediate was performed to minimize the impact of impurities on the final copper catalyzed cyanate installation/cyclization step to afford Effavirenz. Optimization of this step in batch mode for both copper source and ligand identified Cu(NO3)2 and CyDMEDA in a 1:4 molar ratio (20 mol % and 80 mol %, respectively) produced the product in 60% yield. Adaptation of this procedure to flow conditions resulted in poor conversion due to slow in situ reduction of the Cu(II) to Cu(I). Thus, a packed bed reactor of NaOCN and Cu(0) was used. Under these conditions, the ligand and catalyst loading could be reduced without compromising yield. Due to solubility limitations of Cu(NO3)2, Cu(OTf)2 was used with CyDMEDA in 1:2 molar ratio (5 mol % and 10 mol % loading, respectively). Under these optimized conditions, rac-Effavirenz was obtained in 62% isolated yield in reaction time of 1 h. This three-step process provides 45% overall yield of rac-Effavirenz and represents the shortest synthesis of this HIV drug reported to date
STR1
STR1
1H NMR (400 MHz, CDCl3, ppm) δ9.45 (s, 1H), 7.49 (s, 1H), 7.35 (dd, J = 8.5, 1.5 Hz, 1H), 6.86 (d, J = 8.5 Hz, 1H), 1.43-1.36 (m, 1H); 0.93-0.85 (m, 4H);
STR1
13C NMR (100 MHz, CDCl3, ppm) δ 149.2, 133.2, 131.7, 129.2, 127.8, 122.1 (q, JC-F = 286 Hz), 116.3, 115.1, 95.9, 79.6 (q, JC-F = 35 Hz), 66.1, 8.8, 0.6;
STR1
19F NMR (376 MHz, CDCl3, ppm) δ -80.98.
1 T. J. Connolly; A. W.-Y Chan; Z. Ding; M. R. Ghosh; X. Shi; J. Ren, E. Hansen; R. Farr; M. MacEwan; A. Alimardanov; et al, PCT Int. Appl. WO 2009012201 A2 20090122, 2009.
2 (a) Z. Dai, X. Long, B. Luo, A. Kulesza, J. Reichwagen, Y. Guo, (Lonza Ltd), PCT Int. Appl. WO2012097510, 2012; (b) D. D. Christ; J. A. Markwalder; J. M. Fortunak; S. S. Ko; A. E. Mutlib; R. L. Parsons; M. Patel; S. P. Seitz, PCT Int. Appl. WO 9814436 A1 19980409, 1998 (c) C. A. Correia; D. T. McQuade; P. H. Seeberger, Adv. Synth. Catal. 2013, 355, 3517−3521.
Angewandte Chemie International Edition
( Angew. Chem., Int. Ed. 2015,54, 4945−4948).

Volume 54, Issue 16April 13, 2015 Pages 4945–4948

A Concise Flow Synthesis of Efavirenz

  • DOI: 10.1002/anie.201411728
SUPP INFO
STR1
STR1

 NEXT EXAMPLE…………….

 

Wang et al. developed a flow process that uses metal catalyzed hydrogenation of NAB (2-nitro-2′-hydroxy-5′-methylazobenzene) to BTA (2-(2′-hydroxy-5′-methylphenyl)benzotriazole), a commonly used ultraviolet absorber. The major challenge in this process was to optimize the reduction of the diazo functionality over the nitro group and control formation of over reduction side products. The initial screen of metals adsorbed onto a γ-Al2O3 support indicated Pd to be superior to the other metals and also confirmed that catalyst preparation plays an important role in selectivity. To better understand the characteristics of the supported metal catalyst systems, the best performing were analyzed by TEM, XRD, H2-TPR, and N2 adsorption–desorption. Finally, solvents and bases were screened ultimately arriving at the optimized conditions using toluene, 2 equiv n-butylamine over 1% Pd/Al2O3, which provided 90% yield BTA in process with 98% conversion. The process can run over 200 h without a decrease in performance
( ACS Sustainable Chem. Eng. 2015, 3,1890−1896)
.
Abstract Image

The synthesis of 2-(2′-hydroxy-5′-methylphenyl)benzotriazole from 2-nitro-2′-hydroxy-5′-methylazobenzene over Pd/γ-Al2O3 in a fixed-bed reactor was investigated. Pd/γ-Al2O3 catalysts were prepared by two methods and characterized by XRD, TEM, H2-TPR, and N2 adsorption–desorption. Employed in the above reaction, the palladium catalyst impregnated in hydrochloric acid exhibited much better catalytic performance than that impregnated in ammonia–water, which was possibly attributed to the better dispersion of palladium crystals on γ-Al2O3. This result demonstrated that the preparation process of the catalyst was very important. Furthermore, the reaction parameters were optimized. Under the optimized conditions (toluene, NAB/triethylamine molar ratio 1:2, 60 °C, 2.5 MPa hydrogen pressure, 0.23 h–1 liquid hourly space velocity), about 90% yield of 2-(2′-hydroxy-5′-methylphenyl)benzotriazole was obtained. Finally, the time on stream performance of the catalyst was evaluated, and the reaction could proceed effectively over 200 h without deactivation of the catalyst.

Construction of 2-(2′-Hydroxy-5′-methylphenyl)benzotriazole over Pd/γ-Al2O3 by a Continuous Process

ACS Sustainable Chem. Eng., 2015, 3 (8), pp 1890–1896
DOI: 10.1021/acssuschemeng.5b00507
Publication Date (Web): July 06, 2015

NEXT EXAMPLE…………….

 

Continuous Flow-Processing of Organometallic Reagents Using an Advanced Peristaltic Pumping System and the Telescoped Flow Synthesis of (E/Z)-Tamoxifen

continuous flow processing of organometallic reagents

A new enabling technology for the pumping of organometallic reagents such as n-butyllithium, Grignard reagents, and DIBAL-H is reported, which utilises a newly developed, chemically resistant, peristaltic pumping system. Several representative examples of its use in common transformations using these reagents, including metal–halogen exchange, addition, addition–elimination, conjugate addition, and partial reduction, are reported along with examples of telescoping of the anionic reaction products. This platform allows for truly continuous pumping of these highly reactive substances (and examples are demonstrated over periods of several hours) to generate multigram quantities of products. This work culminates in an approach to the telescoped synthesis of (E/Z)-tamoxifen using continuous-flow organometallic reagent-mediated transformations.

https://www.vapourtec.com/flow-chemistry-resource-centre/publications-citing-vapourtec/continuous-flow-processing-of-organometallic-reagents-using-an-advanced-peristaltic-pumping-system-and-the-telescoped-flow-synthesis-of-ez-tamoxifen/

NEXT EXAMPLE…………….

 

Multi-step Continuous Flow Pyrazole Synthesis via a Metal-free Amine-redox Process

A versatile multi-step continuous flow synthesis for the preparation of substituted pyrazoles is presented.

The automated synthesis utilises a metal-free ascorbic acid mediated reduction of diazonium salts prepared from aniline starting materials followed by hydrolysis of the intermediate hydazide and cyclo-condensation with various 1,3-dicarbonyl equivalents to afford good yields of isolated functionalised pyrazole products.

The synthesis of the COX-2 selective NSAID was demonstrated using this approach.

NEXT EXAMPLE…………….

 

Synthesis of a Precursor to Sacubitril Using Enabling Technologies

Continuous flow methodologyhas been used to enhance several steps in the synthesis of a precursor to Sacubitril.

In particular, a key carboethoxyallylation benefited from a reducedprocessing time and improved reproducibility, the latter attributable toavoiding the use of a slurry as in the batch procedure. Moreover, in batchexothermic formation of the organozinc species resulted in the formation ofside products, whereas this could be avoided in flow because heat dissipationfrom a narrow packed column of zinc was more efficient

NEXT EXAMPLE…………….

 

RAFT RAFT (Reversible Addition Fragmentation chain Transfer), a type of controlled radical polymerization, was invented by CSIRO in 1998 but developed in partnership with DuPont over a long term collaboration. Conventional polymerisation is fast but gives a wide distribution of polymer chain lengths. (known as a high polydispersity index ). RAFT is more versatile than other living polymerization techniques, such as atom transfer radical polymerization (ATRP) or nitroxide-mediated polymerization (NMP), it not only leads to polymers with a low polydispersity index and a predetermined molecular weight, but it permits the creation of complex architectures, such as linear block copolymers, comblike, star, brush polymers and dendrimers. Monomers capable of polymerizing by RAFT include styrenes, acrylates, acrylamides, and many vinyl monomers. CSIRO is the owner of the RAFT patents and is actively commercialising the technology. There are 12 licences in force and CSIRO is pursuing interest in a number of fields including human health, agriculture, animal health and personal care. RAFT is the dominant polymerization technique for the creation of polymer-protein or polymer-drug conjugates, permitting (for example) the combination of a polymer exhibiting high solubility with a drug molecule with poor solubility.. Though RAFT can be carried out in batch, it also lends itself to continuous flow processing, as this processing method offers an easy and reproducible scale-up route of the oxygen sensitive RAFT process. The possibility to effectively exclude oxygen using continuous flow reactors in combination with inline degassing methods offers advantages over batch processing at scales beyond the laboratory environment. Challenges associated with the high viscosity of the polymer product solution can be controlled using pressuriseable continuous flow reactor systems. http://www.csiro.au/products/RAFT.html
STR1

Examples………..

Cyclohexaneperoxycarboxylic acid (6,  has been developed as a safe, inexpensive oxidant, with demonstrated utility in a Baeyer−Villiger rearrangement.34 Solutions of cyclohexanecarboxylic acid in hexane and 50% aqueous H2O2 were continuously added to 45% H2SO4 at 50−70 °C and slightly reduced pressure. The byproduct H2O was removed azeotropically, and the residence time in the reactor was 3 h. Processing was adjusted to maintain a concentration of 6 at 17−19%, below the detonable level, and the product was kept as a stable solution in hexane. These operations enhanced the safety margin in preparing 6.

figure

Scheme .  Generation of cyclohexaneperoxycarboxylic acid

Examples………..

Abstract Image

The conversion of a batch process to continuous (flow) operation has been investigated. The manufacture of 4,d-erythronolactone at kilogram scale was used as an example. Fully continuousprocessing was found to be impracticable with the available plant because of the difficulty in carrying out a multiphase isolation step continuously, so hybrid batch–continuous options were explored. It was found that very little additional laboratory or process safety work other than that required for the batch process was required to develop the hybrid process. A hybrid process was chosen because of the difficulty caused by the precipitation of solid byproduct during the isolation stage. While the project was a technical success, the performance benefits of the hybrid process over the batch were not seen as commercially significant for this system.

Multikilogram Synthesis of 4-d-Erythronolactone via Batch andContinuous Processing

Org. Process Res. Dev., 2012, 16 (5), pp 1003–1012

Examples………..

Abstract Image

Continuous Biocatalytic Processes

Org. Process Res. Dev., 2009, 13 (3), pp 607–616
Figure
Scheme . Biotransformation of sodium l-glutamate to γ-aminobutyric acid (GABA) by single-step α-decarboxylation with glutamate decarboxylase

PICS…………..

References

  1.  American Iron and Steel Institute
  2.  Benett, Stuart (1986). A History of Control Engineering 1800-1930. Institution of Engineering and Technology. ISBN 978-0-86341-047-5.
  3.  Ziegler, Gregory R.; Aguilar, Carlos A. (2003). “Residence Time Distribution in a Co-rotating, Twin-screw Continuous Mixer by the Step Change Method”. Journal of Food Engineering(Elsevier) 59 (2-3): 1–7.

Sources and further reading

  • R H Perry, C H Chilton, C W Green (Ed), Perry’s Chemical Engineers’ Handbook (7th Ed), McGraw-Hill (1997), ISBN 978-0-07-049841-9
  • Major industries typically each have one or more trade magazines that constantly feature articles about plant operations, new equipment and processes and operating and maintenance tips. Trade magazines are one of the best ways to keep informed of state of the art developments.

Breaking and Making of Olefins Simultaneously Using Ozonolysis: Application to the Synthesis of Useful Building Blocks and Macrocyclic Core of Solomonamides


Abstract Image

A simple and practical one-pot, two-directional approach to access olefinic esters through simultaneous breaking and making of olefins using ozonolysis of alkenyl aryl selenides is disclosed. The scope of the method with a variety of examples is demonstrated, and the end products obtained here are useful building blocks. As a direct application of the present method, the macrocyclic core of potent anti-inflammatory natural cyclic peptides, solomonamides, is synthesized.

Breaking and Making of Olefins Simultaneously Using Ozonolysis: Application to the Synthesis of Useful Building Blocks and Macrocyclic Core of Solomonamides

CSIR-National Chemical Laboratory, Division of Organic Chemistry, Dr. Homi Bhabha Road, Pune 411008, India
Org. Lett., 2015, 17 (9), pp 2090–2093
DOI: 10.1021/acs.orglett.5b00637
Publication Date (Web): April 14, 2015
Copyright © 2015 American Chemical Society
Figure
GENERAL METHOD
 

Dr. D. Srinivasa Reddy

Continuous ruthenium-catalyzed methoxycarbonylation with supercritical carbon dioxide


 

Catal. Sci. Technol., 2016, Advance Article
DOI: 10.1039/C5CY01883H, Paper
Stefan Christiaan Stouten, Timothy Noel, Qi Wang, Matthias Beller, Volker Hessel
The methoxycarbonylation of cyclohexene with carbon dioxide over a ruthenium catalyst was realized in a micro flow system under supercritical conditions.
Continuous ruthenium-catalyzed methoxycarbonylation with supercritical carbon dioxide
The methoxycarbonylation of cyclohexene with carbon dioxide over a ruthenium catalyst was realized in a micro flow system under supercritical conditions. Instead of the toxic and flammable carbon monoxide, this process utilizes carbon dioxide, thereby avoiding issues with bulk transportation of carbon monoxide as well as eliminating the need for safety precautions associated with the use of carbon monoxide. Obtained was a 77% yield of the ester product at 180 °C, 120 bar and with a 90 min residence time, which is over five times faster than for the same reaction performed under subcritical conditions in batch. An important factor for the performance of the system was to have a sufficiently polar supercritical mixture, allowing the catalyst to dissolve well. The optimal temperature for the reaction was 180 °C, as the activity of the system dropped considerably at higher temperatures, most likely due to catalyst deactivation.

Department of Chemical Engineering and Chemistry

ir. S.C. (Stefan) Stouten –

Stouten, ir. S.C.
Address:
Technische Universiteit Eindhoven
P.O. Box 513
5600 MB EINDHOVEN
Department:
Department of Chemical Engineering and Chemistry
Section:
Micro Flow Chemistry and Process Technology
Positioncategory:
doctoral candidate (PhD) (PhD Stud.)
Position:
doctoral candidate
Room:
STW 0.
Email:
s.stouten@tue.nl

 

 

 

Volker Hessel

prof.dr. V. (Volker) Hessel

Hessel, prof.dr. V.
Address:
Technische Universiteit Eindhoven
P.O. Box 513
5600 MB EINDHOVEN
Chair:
Micro Flow Chemistry and Process Technology
Department:
Department of Chemical Engineering and Chemistry
Section:
Micro Flow Chemistry and Process Technology
Positioncategory:
Professor (HGL)
Position:
Full Professor
Room:
STW 1.45
Tel:
+31 40-247 2973
Tel (internal):
2973
Email:
v.hessel@tue.nl

////////Continuous,  ruthenium-catalyzed,  methoxycarbonylation, supercritical carbon dioxide, flow reactor

Cutting Edge of Pharmaceutical Nanotechnology


Nanoscience is the engineering of functional systems at the molecular scale. This covers both current work and concepts that are more advanced. In its original sense, nanotechnology refers to the projected ability to construct items from the bottom up, using techniques and tools being developed today to make complete, high performance products. Some researches and findings in the field of Nanoscience are selected and expended here: “Fabrication of Novel Poly (ethylene terephthalate)/TiO2 Nanofibers by Electrospinning and their Photocatalytic Activity” reports on functional nanocomposites PET/TiO2 nanofibers membranes prepared via simple electrospinning and hydrothermal processing, involving preparation of titania precursor sol solution, electrospinning the homogeneous mixture of PET solution and sol solution, and in-situ growth of nanoscale TiO2 within PET nanofibers in hot water.

“Oxidation of glyoxal to glyoxalic acid by Prepared Nano-Au/C catalysts” describes that Nano-Au/C catalysts were obtained by loading the gold nanoparticles which were prepared by photochemical reduction method to the activated carbon, and were used for the catalytic oxidation reaction of glyoxal into glyoxylic acid.

“Preparation of the Al-CNT (Carbon Nanotubes) Compound Material by High Energy Milling” using high energy ball milling (HEM), researched the technology of preparation of Al-CNT compound material.

“Theoretical Prediction of Tensile Behavior of Single-Walled Carbon Nanotubes” establishes a link between molecular and continuum mechanics based on the Morse potential function.

In the paper “Research on the stress-relaxation characteristics of cancer cells based on Atomic Force Microscope”, the AFM indentation experiments are carried out on two different transferring characteristic cancer cells (Anip-937 and AGZY-83a) under physiological conditions using the expansion of atomic force microscope (AFM) indentation and the improvement of Hertz model.

“Application of Nanoscale Zero-valent Iron (nZVI) to Enhance Microbial Reductive Dechlorination of TCE: A Feasibility Study” evaluates the feasibility of nanoscale zero-valent iron (nZVI) application to enhance microbial reductive dechlorination of trichloroethylene (TCE).

“Hydrothermal Processing-Assisted Synthesis of Nanocrystalline YFeO3 and its Visible-Light Photocatalytic Activity” finds that the single phase YFeO3 can be obtained through the calcination of hydrothermally processed YFeO3 precursors at 800°C, and the resulting product has a spherical shape and uniform size distribution.

“Preparation and exothermic characterization of HTPB-coated aluminum nano-powders prepared by laser-induction hybrid heating” calculates the temperature distribution of aluminum with the heating time and the distance from the crucible centre based on the ANSYS software.

“Application Thinking of Nanotechnology in Acupuncture” discusses the application of nanotechnology methods for the researches on meridians of Chinese medicine, acupoint catgut embedding therapy (ACET) and therapeutic mechanism in acupuncture field.

“The Research of Conjunction Calculated Relationships between Proteins with Gold Nanoparticles” researches the conjunction calculated relationship between proteins and gold nanoparticles.

“Engineered nanoparticles as precise drug delivery systems”- Nanoparticles, an evolvement of nanotechnology, are increasingly considered as a potential candidate to carry therapeutic agents safely into a targeted compartment in an organ, particular tissue or cell.

“Dendrimers: emerging polymers for drug-delivery systems”, the unique properties associated with these dendrimers such as uniform size, high degree of branching, water solubility, multivalency, welldefined molecular weight and available internal cavities make them attractive for biological and drug-delivery applications.

“Strategies for in vivo siRNA delivery in cancer”- As a research tool, siRNA has proven to be highly effective in silencing specific genes and modulating intracellular signaling pathways.

“Rapid delivery of drug carriers propelled and navigated by catalytic nanoshuttles”- nanoshuttles’ navigation ability is illustrated by the transport of the drug carriers through a microchannel from the pick-up to the release microwell. Such ability of nanomotors to rapidly deliver drug-loaded polymeric particles and liposomes to their target destination represents a novel approach towards transporting drug carriers in a target-specific manner.

“Multigram-scale fabrication of monodisperse conducting polymer and magnetic carbon nanoparticles” is an emerging tool for cutting edge nanotechnology approach.

Cutting Edge of Pharmaceutical Nanotechnology

Suryakanta Swain*

Suryakanta Swain
Roland Institute of Pharmaceutical Sciences
Department of Pharmaceutics
Khodasinghi, Berhampur-760 010 (Ganjam)
Odisha, India
Email: swain_suryakant@yahoo.co.in

Roland Institute of Pharmaceutical Sciences, Department of Pharmaceutics, IndiaCitation: Swain S (2012) Cutting Edge of Pharmaceutical Nanotechnology. Pharmaceut Reg Affairs 1:e110. doi: 10.4172/2167-7689.1000e110

http://www.omicsgroup.org/journals/cutting-edge-of-pharmaceutical-nanotechnology-2167-7689.1000e110.php?aid=8206

/////////////Cutting Edge,  Pharmaceutical Nanotechnology

TOFACITINIB 的合成, トファシチニブ, Тофацитиниб, توفاسيتين يب SPECTRAL VISIT


Tofacitinib Citrate, 的合成

托法替布,  トファシチニブクエン酸塩, Тофацитиниба Цитрат

 3-{(3R,4R)-4-methyl-3-[methyl-(7H-pyrrolo[2,3-d]pyrimidin-4-yl)-amino]-piperidin-1-yl}-3-oxo-propionitrile citrate salt

CAS : 540737-29-9

ROTATION +

Tofacitinib; Tasocitinib;

477600-75-2 base ; CP-690550;

3-((3R,4R)-4-methyl-3-(methyl(7H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)piperidin-1-yl)-3-oxopropanenitrile;

3-{(3R,4R)-4-methyl-3-rmethyl-(7H-pyrrolor2,3-dlpyrimidin-4-yl)-amino1- piperidin-1-yl}-3-oxo-propionitrile mono citrate salt

CP 690550 Tofacitinib; CP-690550; CP-690550-10; Xeljanz; Jakvinus; Tofacitinib citrate

Trademarks: Xeljanz; Jakvinus

MF: C16H20N6O

CAS : 477600-75-2 BASE ; 540737-29-9(citrate) 3-[(3R,4R)-4-methyl-3-[methyl(7H-pyrrolo[2,3-d]pyrimidin-4-yl)amino]piperidin-1-yl]-3-oxopropanenitrile

Molecular Weight: 312.369

SMILES: C[C@@H]1CCN(C[C@@H]1N(C)C2=NC=NC3=C2C=CN3)C(=O)CC#N

Activity: Treatment of Rheumatoid Arthritis; RA Treatment, JAK Inhibitor; Protein Kinase Inhibitor; JAK3 Inhibitor; Janus Kinase 3 Inhibitor; JAK-STAT Signaling Pathway; JAK1 Kinase Inhibitor; Selective Immunosuppressants

Status: Launched 2012

Originator: Pfizer
Pfizer Inc’s oral JAK inhibitor tofacitinib was approved on November 6, 2012 by US FDA for the treatment of rheumatoid arthritis.
सुकून उतना ही देना प्रभू, जितने से जिंदगी चल जाये।औकात बस इतनी देना,कि औरों का भला हो जाये।………..P.S. : The views expressed are my personal and in no-way suggest the views of the professional body or the company that I represent.

Tofacitinib (trade names Xeljanz and Jakvinus, formerly tasocitinib,[1] CP-690550[2]) is a drug of the janus kinase (JAK) inhibitor class, discovered and developed by Pfizer. It is currently approved for the treatment of rheumatoid arthritis (RA) in the United States,Russia, Japan and many other countries, is being studied for treatment of psoriasis, inflammatory bowel disease, and other immunological diseases, as well as for the prevention of organ transplant rejection.

An Improved and Efficient Process for the Preparation of Tofacitinib Citrate

Publication Date (Web): November 17, 2014 (Article)
DOI: 10.1021/op500274j
 
MS m/z 313 (M+ + 1);
mp 201–202 °C;  
1H NMR (CDCl3) δ 8.34 (s, 1H), δ 7.38 (d, 1H, J = 2.4 Hz), δ 6.93 (d, 1H, J = 2.4 Hz), δ 4.97 (m, 1H), δ 3.93–4.03 (m, 4H), δ 3.66 (m, 1H), δ 3.50 (m, 4H), δ 2.91 (d, 2H, J = 15.6 Hz), δ 2.80 (t, 2H, J = 12.8 Hz), δ 2.55 (m, 1H), δ 1.99 (m, 1H), δ 1.77 (m, 1H), δ 1.13–1.18 (m, 3H).
Print
09338-acsnews1-pfizercxd
TEAMWORK
Part of the Pfizer group responsible for Xeljanz: Front row, from left: Sally Gut Ruggeri, Chakrapani Subramanyam, Eileen Elliott Mueller, and Frank Busch. Second row, from left: Matthew Brown, Mark Flanagan, and Robert Dugger. Back row, from left: Elizabeth Kudlacz and Douglas Ball.
Credit: Pfizer
Mark Flanagan, who was on the team at Pfizer that discovered Xeljanz, (tofacitinib citrate), an oral treatment for rheumatoid arthritis, remembers testing the drug in a rat model and seeing the drug decrease the level of inflammation in the rats’ footpads. “What we look for is physical measurements of the size of the joint. In the control animals, there was quite a bit of inflammation in the joints, whereas animals treated with different doses of the drug showed a dose-dependent decrease in the size of the joint. “Tofacitinib showed robust efficacy in the first such study run. I can remember the excitement that this data generated on the team,” he says.

Tofacitinib, chemically known as (3R,4R)-4-methyl-3-(methyl-7H-pyrrolo [2,3- d]pyrimidin-4-ylamino)-B-oxo-l -piperidinepi panenitrile, is represented Formula I. Tofacitinib citrate, a janus kinase inhibitor, is approved as XELJANZ® tablets for treatment .of rheumatoid arthritis.

Figure imgf000002_0001

Various intermediates and processes for preparation of tofacitinib are disclosed in patents like US7301 023 and US8232394.

Figure imgf000020_0001

Formula I or isomers or a mixture of isomers thereof by following any method provided in the prior art, for example, by following Example 14 of U.S. Patent No. RE41,783 or by following Example 6 of U.S. Patent No. 7,301,023. Tofacitinib of Formula I or isomers of tofacitinib or a mixture of isomers thereof may be converted into a salt by following any method provided in the prior art, for example, by following Example 1 of U.S. Patent No. 6,965,027 or by following Example 1 or Example 8 of PCT Publication No. WO 2012/135338. The potential significance of JAK3 inhibition was first discovered in the laboratory of John O’Shea, an immunologist at the National Institute of Arthritis and Musculoskeletal and Skin Diseases of the National Institutes of Health (NIH).[5] In 1994, Pfizer was approached by the NIH to form a public-private partnership in order to evaluate and bring to market experimental compounds based on this research.[5] Pfizer initially declined the partnership but agreed in 1996, after the elimination of an NIH policy dictating that the market price of a product resulting from such a partnership would need to be commensurate with the investment of public taxpayer revenue and the “health and safety needs of the public.”[5] The drug discovery, preclinical development, and clinical development of tofacitinib took place exclusively at Pfizer.[6] In November 2012, the U.S. Food and Drug Administration (FDA) approved tofacitinib for treatment of rheumatoid arthritis. Once on the market, rheumatologists complained that the $2,055 a month wholesale price was too expensive, though the price is 7% less than related treatments.[6] A 2014 study showed that tofacitinib treatment was able to convert white fat tissues into more metabolically active brown fat, suggesting it may have potential applications in the treatment of obesity.[7] It is an inhibitor of the enzyme janus kinase 1 (JAK1) and janus kinase 3 (JAK 3) , which means that it interferes with the JAK-STAT signaling pathway, which transmits extracellular information into the cell nucleus, influencing DNA transcription.[3] Recently it has been shown in a murine model of established arthritis that tofacitinib rapidly improved disease by inhibiting the production of inflammatory mediators and suppressing STAT1-dependent genes in joint tissue. This efficacy in this disease model correlated with the inhibition of both JAK1 and 3 signaling pathways, suggesting that tofacitinib may exert therapeutic benefit via pathways that are not exclusive to inhibition of JAK3.[4]

Preparation of 3-{(3R,4R)-4-methyl-3-[methyl-(7H-pyrrolo[2,3-d]pyrimidin-4-yl)-amino]-piperidin-1-yl}-3-oxo-propionitrile citrate salt (Tofacitinib citrate, Xeljanz, CP-690550-10)
To a round-bottomed flask fitted with a temperature probe, condenser, nitrogen source, and heating mantle, methyl-[(3R,4R)-4-methyl-piperidin-3-yl]-(7H-pyrrolo[2,3-d]pyrimidin-4-yl)-amine (5.0 g, 20.4 mmol) was added followed by 1-butanol (15 mL), ethyl cyanoacetate (4.6 g, 40.8 mmol), and DBU (1.6 g, 10.2 mmol). The resulting amber solution was stirred at 40 °C for 20 h. Upon reaction completion, citric acid monohydrate (8.57 g, 40.8 mmol) was added followed by water (7.5 mL) and 1-butanol (39.5 mL). The mixture was heated to 81 °C and held at that temperature for 30 min. The mixture was then cooled slowly to 22 ºC and stirred for 2 h. The slurry was filtered and washed with 1-butanol (20 mL). The filter cake was dried in a vacuum oven at 80 °C to afford 9.6 g (93%) of tofacitinib citrate as an off-white solid.
1H NMR (500 MHz, d6-DMSO): δ 8.14 (s, 1H), 7.11 (d, J=3.6 Hz, 1H), 6.57 (d, J=3.6 Hz, 1H), 4.96 (q, J=6.0 Hz, 1H), 4.00-3.90 (m, 2H), 3.80 (m, 2H), 3.51 (m, 1H), 3.32 (s, 3H), 2.80 (Abq, J=15.6 Hz, 2H), 2.71 (Abq, J=15.6 Hz, 2H), 2.52-2.50 (m, 1H), 2.45-2.41 (m, 1H), 1.81 (m, 1H), 1.69-1.65 (m, 1H), 1.04 (d, J=6.9 Hz, 3H).
सुकून उतना ही देना प्रभू, जितने से जिंदगी चल जाये।औकात बस इतनी देना,कि औरों का भला हो जाये।………..P.S. : The views expressed are my personal and in no-way suggest the views of the professional body or the company that I represent.
PAPER
3-((3R,4R)-4-Methyl-3-(methyl(7H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)piperidin-1-yl)-3-oxopropanenitrile (1) Monocitrate
J. Med. Chem., 2010, 53 (24), pp 8468–8484
DOI: 10.1021/jm1004286
1monocitrate as a white crystalline solid (mp = 201 dec).
LRMS: m/z 313.2 (MH+).
1H NMR (400 MHz) (D2O) δ HOD: 0.92 (2 H, d, J = 7.2 Hz), 0.96 (1 H, d, J = 7.6 Hz), 1.66 (1 H, m), 1.80 (1 H, m), 2.37 (1 H, m), 2.58 (2 H, 1/2 ABq, J = 15.4 Hz), 2.70 (2 H, 1/2 ABq, J = 15.4 Hz), 3.23 (2 H, s), 3.25 (1 H, s), 3.33 (1 H, m), 3.46 (1 H, m), 3.81 (4 H, m), 4.55 (1 H, m), 6.65 (1 H, d, J = 3.2 Hz), 7.20 (1 H, t, J = 3.2 Hz), 8.09 (1 H, m).
Anal. Calcd for C22H28N6O8: C, 52.38; H, 5.59; N, 16.66. Found: C, 52.32; H, 5.83; N, 16.30. For additional characterization of the monocitrate salt of 1 see WO 03/048162.
NMR PREDICT
References:
Weiling Cai, James L. Colony,Heather Frost, James P. Hudspeth, Peter M. Kendall, Ashwin M. Krishnan,Teresa Makowski, Duane J. Mazur, James Phillips, David H. Brown Ripin, Sally Gut Ruggeri, Jay F. Stearns, and Timothy D. White; Investigation of Practical Routes for the Kilogram-Scale Production of cis-3-Methylamino-4-methylpiperidinesOrganic Process Research & Development 2005, 9, 51−56
Ripin, D. H.B.; 3-amino-piperidine derivatives and methods of manufacture, US patent application publication, US 2004/0102627 A1
Ruggeri, Sally, Gut;Hawkins, Joel, Michael; Makowski, Teresa, Margaret; Rutherford, Jennifer, Lea; Urban,Frank,John;Pyrrolo[2,3-d]pyrimidine derivatives: their intermediates and synthesis, PCT pub. No. WO 2007/012953 A 2, US20120259115 A1, United States Patent US8232393. Patent Issue Date: July 31, 2012
Kristin E. Price, Claude Larrive´e-Aboussafy, Brett M. Lillie, Robert W. McLaughlin, Jason Mustakis, Kevin W. Hettenbach, Joel M. Hawkins, and Rajappa Vaidyanathan; Mild and Efficient DBU-Catalyzed Amidation of Cyanoacetates, Organic Letters, 2009, vol.11, No.9, 2003-2006
MORE NMR PREDICT

tofacitinib Molbase str

Tofacitinib TOFA  1H proton NMR spectra

tofacitinib 1h values

13C NMR PREDICT  TOFA  13C NMR spectra

 

 

SEE…….https://newdrugapprovals.org/2015/07/24/tofacitinib-%E7%9A%84%E5%90%88%E6%88%90-spectral-visit/

 

 

COSY PREDICT COSY NMR prediction सुकून उतना ही देना प्रभू, जितने से जिंदगी चल जाये।औकात बस इतनी देना,कि औरों का भला हो जाये।………..P.S. : The views expressed are my personal and in no-way suggest the views of the professional body or the company that I represent.

SEE………http://orgspectroscopyint.blogspot.in/2014/12/tofacitinib-citrate.html

 

NMR PICTURE FROM THE NET

tofacitinib ABMOLE NMR BASE

 

PAPER

Volume 54, Issue 37, 11 September 2013, Pages 5096–5098

Asymmetric total synthesis of Tofacitinib

  • a Laboratory of Asymmetric Synthesis, Chemistry Institute of Natural Resources, University of Talca, P.O. Box 747, Talca, Chile
  • b Laboratory of Natural Products, Department of Chemistry, University of Antofagasta, P.O. Box 170, Antofagasta, Chile

http://dx.doi.org/10.1016/j.tetlet.2013.07.042

Abstract

A novel stereoselective synthesis of Tofacitinib (CP-690,550), a Janus tyrosine kinase (JAK3) specific inhibitor, has been achieved starting from (5S)-5-hydroxypiperidin-2-one in 10 steps from 2 with a 9.5% overall yield. The potentiality of this synthetic route is the obtention of tert-butyl-(3S,4R)-3-hydroxy-4-methylpiperidine-1-carboxylate (6b) as a new chiral precursor involved in the synthesis of CP690,550, in a three-step reaction, without epimerizations, rather than the 5 or more steps used in described reactions to achieve this compound from analogues of 6b.


Graphical abstract

Image for unlabelled figure

…………………. Tofacitinib synthesis: US2001053782A1

Tofacitinib synthesis: WO2002096909A1
 
Tofacitinib synthesis: Org Process Res Dev 2014, 18(12), 1714-1720 (also from a chinese publication, same procedure just slight changes in reagents/conditions)
 
References:
1. Blumenkopf, T. A.; et. al. Pyrrolo[2,3-d]pyrimidine compounds. US2001053782A1
2. Flanagan, M. E.; et. al. Optical resolution of (1-benzyl-4-methylpiperidin-3-yl) -methylamine and the use thereof for the preparation of pyrrolo 2,3-pyrimidine derivatives as protein kinases inhibitors. WO2002096909A1
3. Das, A.; et. al. An Improved and Efficient Process for the Preparation of Tofacitinib Citrate. Org Process Res Dev2014, 18(12), 1714-1720.

 

PATENT https://www.google.co.in/patents/WO2003048162A1?cl=en The crystalline form of the compound of this invention 3-{4-methyl-3-[methyl- (7H-pyrrolot2,3-d]pyrimidin-4-yl)-amino]-piperidin-1-yl}-3-oxo-propionitrile mono citrate salt is prepared as described below. Scheme 1

Figure imgf000005_0001
Figure imgf000005_0002

Scheme 2

Figure imgf000006_0001
Figure imgf000006_0002
Figure imgf000006_0003
Figure imgf000006_0004

Example 1 3-{(3R,4R)-4-methyl-3-rmethyl-(7H-pyrrolor2,3-dlpyrimidin-4-yl)-amino1- piperidin-1-yl}-3-oxo-propionitrile mono citrate salt Ethanol (13 liters), (3R, 4R)-methyl-(4-methyl-piperidin-3-yl)-(7H-pyrrolo[2,3- d]pyrimidin-4-yl)-amine (1.3 kg), cyano-acetic acid 2,5-dioxo-pyrrolidin-1-yl ester (1.5 kg), and triethylamine (1.5 liters) were combined and stirred at ambient temperature. Upon reaction completion (determined by High Pressure Liquid Chromotography (HPLC) analysis, approximately 30 minutes), the solution was filtered, concentrated and azeotroped with 15 liters of methylene chloride. The reaction mixture was washed sequentially with 12 liters of 0.5 N sodium hydroxide solution, 12 liters of brine and 12 liters of water. The organic layer was concentrated and azeotroped with 3 liters of acetone (final pot temperature was 42°C). The resulting solution was cooled to 20°C to 25°C followed by addition of 10 liters of acetone. This solution was filtered and then aqueous citric acid (0.8 kg in 4 liters of water) added via in-line filter. The reaction mixture was allowed to granulate. The slurry was cooled before collecting the solids by filtration. The solids were dried to yield 1.9 kg (71 %) (3R, 4R)- 3-{4-Methyl-3-[methyl-(7H-pyrrolo[2,3-d]pyrimidin-4-yl)-amino]-piperidin-1-yl}-3-oxo- propionitrile mono citrate. This material was then combined with 15 liters of a 1:1 ratio of ethanol/water and the slurry was agitated overnight. The solids were filtered and dried to afford 1.7 kg (63% from (3R, 4R)-methyl-(4-methyl-piperidin-3-yl)-(7H- pyrrolo[2,3-d]pyrimidin-4-yl)-amine) of the title compound as a white crystalline solid. 1H NMR (400 MH2)(D20) δ HOD: 0.92 (2H, d, J = 7.2 Hz), 0.96 (1H, d, J = 7.6 Hz), 1.66 (1H, m), 1.80 (1H, m), 2.37 (1H, m), 2.58 (2H, 1/2 ABq, J = 15.4 Hz), 2.70 (2H, 3 ABq, J = 154 Hz), 3.23 (2H, s), 3.25 (1H, s), 3.33 (1H, m), 3.46 (1H, m), 3.81 (4H, m), 4.55 (1 H, m), 6.65 (1 H, d, J = 3.2 Hz), 7.20 (1 H, t, J = 3.2 Hz), 8.09 (1 H, m).

 

Patent

http://www.google.co.in/patents/EP1913000A2?cl=en Example 10 Preparation of methyl-[(3R, 4R)-4-methyl-piperidin-3-yl]-(7H-pyrrolo[2,3-d]pyrimidin-4-yl)-amine:

KEY INTERMEDIATE

To a clean, dry, nitrogen-purged 2 L hydrogenation reactor were charged 20 wt% Pd(OH)2/C (24.0 g, 50% water wet), water (160 ml), isopropanol (640 ml), (1-benzyl-4-methyl-piperidin-3-yI)-methyi- (7H-pyrrolo[2,3-d]pyrimidin-4-yl)-amine (160.0 g, 0.48 mol), and acetic acid (28.65 g, 0.48 mol). The reactor was purged with three times at 50 psi with nitrogen and three times at 50 psi with hydrogen. Once purging was complete, the reactor was heated to 45-55°C and pressurized to 50 psi with hydrogen through a continuous feed. The hydrogen uptake was monitored until no hydrogen was consumed for 1 hour. The reactor was cooled to 20-300C and purged three times at 50 psi with nitrogen. The reaction mixture was filtered through wet Celite and the filtrate was sent to a clean, dry, nitrogen-purged vessel. A solution of sodium hydroxide (39.33 g) in water (290 ml) was charged and the mixture was stirred for a minimum of 1 hour then heated to 75-900C. The isopropanol was removed by distillation. The reaction mixture was cooled to 20-30°C and 2-methyltetrahydrofuran (1.6 L) was added. The aqueous layer was drained off and the 2-methyltetrahydrofuran was displaced with toluene (1.6 L). The distillation was continued until the final volume was 800 ml. The slurry was cooled to 20-30°C and held for a minimum of 7 hours. The resulting solids were isolated by filtration and washed with toluene (480 ml). After drying under vacuum between 40-50DC for a minimum of 24 hours with a slight nitrogen bleed 102.3 g (87.3%) of the title compound were isolated. Mp 158.6-159.8°C. 1H NMR (400 MHz, CDCI3): δ 11.38 (bs, 1H), 8.30 (s, 1H), 7.05 (d, J=3.5 Hz, 1H), 6.54 (d, J=3.5 Hz, 1H), 4.89-4.87 (m, 1H), 3.39 (s, 3H), 3.27 (dd, J=12.0, 9.3 Hz, 1 H), 3.04 (dd, J=12.0, 3.9 Hz, 1H), 2.94 (td, J=12.6, 3.1 Hz, 1H0, 2.84 (dt, J=12.6, 4.3 Hz, 1H), 2.51-2.48 (m, 1H), 2.12 (bs, 2H), 1.89 (ddt, J=13.7, 10.6, 4 Hz, 1 H), 1.62 (dq, J=13.7, 4Hz, 1 H), 1.07 (d, J=7.3 Hz, 3H). 13C NMR (400 MHz, CDCI3): δ 157.9, 152.0, 151.0, 120.0, 103.0, 102.5, 56.3, 46.2, 42.4, 34.7, 33.4, 32.4, 14.3. KEY INT

 

Example 11 Preparation of 3-{(3R, 4R)-4-methyl-3-[methyl-(7H-pyrrolo[2,3-d]pyrimidin-4-yl)-amino]-piperidin-1-yl}-3- oxo-propionitrile….TOFACITINIB BASE

 

To a clean, dry, nitrogen-purged 1.0 L reactor were charged methyl-(4-methyl-piperidin-3-yI)-(7H- pyrroIo[2,3-d]pyrimidin-4-yl)-amine (32.0 g, 0.130 mol), toluene (160 ml), ethyl cyanoacetate (88.53 g, 0.783 mol) and triethyl amine (26.4 g, 0.261 mol). The reaction was heated to 1000C and held for 24 hours. The reaction was washed with water (160 ml). The organic layer concentrated to a volume of 10 ml and water (20 ml) was added. The residual toluene was removed by distillation and the mixture was cooled to room temperature. Acetone (224 ml) was added followed by citric acid (27.57 g, 0.144 mol) in water (76 ml). The resulting slurry was stirred for 7 hours. The solids were isolate by filtration, washed with acetone (96 ml), and dried under vacuum to afford 42.85 g (65.3%) of the title compound. Example 13 Preparation of 3-{(3R, 4R)~4-methyl-3-[methyl-(7H-pyrrolo[2,3-d]pyrimidin-4-yl)-amino]-piperidin-1-yl}-3-oxo- propionitrile citrate salt:…………..TOFACITINIB CITRATE To a clean, dry, nitrogen-purged 500 ml reactor were charged methyl-(4-methyl-piperidin-3-yl)-(7H- pyrrolo[2,3-d]pyrimidin-4-yl)-amine (25.0 g, 0.102 mol) and methylene chloride (250 ml). The mixture was stirred at room temperature for a minimum of 2.5 hours. To a clean, dry, nitrogen-purged 1 L reactor were charged cyanoacetic acid (18.2 g, 0.214 mol), methylene chloride (375 ml), and triethyl amine (30.1 ml, 0.214 mol). The mixture was cooled to -15.0— 5.00C over one hour and trimethylacetyl chloride (25.6 ml, 0.204 mol) was added at a rate to maintain the temperature below O0C. The reaction was held for a minimum of 2.5 hours, then the solution of the amine was added at a rate that maintained the temperature below O0C. After stirring for 1 hour, the mixture was warmed to room temperature and 1 M sodium hydroxide (125 ml) was added. The organic layer was washed with water (125 ml) The methylene chloride solution.was displaced with acetone until a volume of 500 ml and a temperature of 55-650C had been achieved. Water (75 ml) was charged to the mixture while maintaining the temperature at 55-65°C. A solution of citric acid (20.76 g, 0.107 mol) in water (25.0) was charged and the mixture was cooled to room temperature. The reactor was stirred for a minimum of 5 hours and then the resulting solids were isolated by filtration and washed with acetone (2×75 ml), which was sent to the filter. The salt was charged into a clean, dry, nitrogen-purged 1L reactor with 2B ethanol (190 ml) and water (190 ml). The slurry was heated to 75-850C for a minimum of 4 hours. The mixture was cooled to 20-300C and stirred for an additional 4 hours. The solids were isolated by filtration and washed with 2B ethanol (190 ml). After drying in a vacuum oven at 500C with a slight nitrogen bleed, 34.6 g (67.3%) of the title compound were isolated. 1H NMR (500 MHz, CZ6-DMSO): δ 8.14 (s, 1 H), 7.11 (d, J=3.6 Hz, 1 H), 6.57 (d, J=3.6 Hz, 1 H), 4.96 (q, J=6.0 Hz, 1 H), 4.00-3.90 (m, 2H), 3.80 (m, 2H), 3.51 (m, 1 H), 3.32 (s, 3H), 2.80 (Abq, J=15.6 Hz, 2H), 2.71 (Abq, J=15.6 Hz, 2H), 2.52-2.50 (m, 1 H), 2.45-2.41 (m, 1 H), 1.81 (m, 1 H), 1.69-1.65 (m, 1 H), 1.04 (d, J=6.9 Hz, 3H)

 

 

PAPER

Org. Lett., 2009, 11 (9), pp 2003–2006
DOI: 10.1021/ol900435t

http://pubs.acs.org/doi/full/10.1021/ol900435t Figure

 

PATENT

http://www.omicsonline.org/open-access/advances-in-the-inhibitors-of-janus-kinase-2161-0444.1000540.php?aid=29799   …………….. सुकून उतना ही देना प्रभू, जितने से जिंदगी चल जाये।औकात बस इतनी देना,कि औरों का भला हो जाये।………..P.S. : The views expressed are my personal and in no-way suggest the views of the professional body or the company that I represent.

Clinical trials

Rheumatoid arthritis

Phase II clinical trials tested the drug in rheumatoid arthritis patients that had not responded to DMARD therapy. In a tofacitinib monotherapy study, the ACR score improved by at least 20% (ACR-20) in 67% of patients versus 25% who received placebo; and a study that combined the drug with methotrexate achieved ACR-20 in 59% of patients versus 35% who received methotrexate alone. In a psoriasis study, the PASI score improved by at least 75% in between 25 and 67% of patients, depending on the dose, versus 2% in the placebo group.[8] The most important side effects in Phase II studies were increased blood cholesterol levels (12 to 25 mg/dl LDL and 8 to 10 mg/dl HDL at medium dosage levels) andneutropenia.[8] Phase III trials testing the drug in rheumatoid arthritis started in 2007 and are scheduled to run until January 2015.[9] In April 2011, four patients died after beginning clinical trials with tofacitinib. According to Pfizer, only one of the four deaths was related to tofacitinib.[10] By April 2011, three phase III trials for RA had reported positive results.[11] In November 2012, the U.S. FDA approved tofacitinib “to treat adults with moderately to severely active rheumatoid arthritis who have had an inadequate response to, or who are intolerant of, methotrexate.”[12]

Psoriasis

As of April 2011 a phase III trial for psoriasis is under way.[11]

Alopecia

In June 2014, scientists at Yale successfully treated a male patient afflicted with alopecia universalis. The patient was able to grow a full head of hair, eyebrows, eyelashes, facial, armpit, genitalia and other hair. No side effects were reported in the study.[13]

Ulcerative colitis

The OCTAVE study of Tofacitinib in Ulcerative Colitis started in 2012. It is currently enrolling patients, though the NIH trials page states that they expect the trial to close in June 2015.[14]

Vitiligo

In a June 2015 study, a 53-year-old woman with vitiligo showed noticeable improvement after taking tofacitinib for five months.[15]

Development of Safe, Robust, Environmentally Responsible Processes for New Chemical Entities

– Dr. V. Rajappa, Director & Head-Process R&D, Bristol-Myers Squibb, India

A PRESENTATION

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  1. Herper, Matthew (2 March 2011). “Why Pfizer’s Biggest Experimental Drug Got A Name Change”. Forbes. Retrieved 3 March 2011.
  2.  Kremer, J. M.; Bloom, B. J.; Breedveld, F. C.; Coombs, J. H.; Fletcher, M. P.; Gruben, D.; Krishnaswami, S.; Burgos-Vargas, R. N.; Wilkinson, B.; Zerbini, C. A. F.; Zwillich, S. H. (2009). “The safety and efficacy of a JAK inhibitor in patients with active rheumatoid arthritis: Results of a double-blind, placebo-controlled phase IIa trial of three dosage levels of CP-690,550 versus placebo”. Arthritis & Rheumatism 60 (7): 1895–1905. doi:10.1002/art.24567. PMID 19565475. edit
  3.  “Tasocitinib”. Drugs in R&D 10 (4): 271–284. 2010. doi:10.2165/11588080-000000000-00000. PMC 3585773. PMID 21171673. edit
  4.  Ghoreschi, K.; Jesson, M. I.; Li, X.; Lee, J. L.; Ghosh, S.; Alsup, J. W.; Warner, J. D.; Tanaka, M.; Steward-Tharp, S. M.; Gadina, M.; Thomas, C. J.; Minnerly, J. C.; Storer, C. E.; Labranche, T. P.; Radi, Z. A.; Dowty, M. E.; Head, R. D.; Meyer, D. M.; Kishore, N.; O’Shea, J. J. (2011). “Modulation of Innate and Adaptive Immune Responses by Tofacitinib (CP-690,550)”. J Immunol. 186 (7): 4234–4243. doi:10.4049/jimmunol.1003668. PMC 3108067. PMID 21383241. edit
  5. ^ Jump up to:a b c “Seeking Profit for Taxpayers in Potential of New Drug”, Jonathan Weisman, New York Times, March 18, 2013
  6. Ken Garber (9 January 2013). “Pfizer’s first-in-class JAK inhibitor pricey for rheumatoid arthritis market”. Nature Biotechnology 31 (1): 3–4. doi:10.1038/nbt0113-3. PMID 23302910.
  7. Jump up^ Moisan A, et al. White-to-brown metabolic conversion of human adipocytes by JAK inhibition. Nature Cell Biology, 8 December 2014. DOI 10.1038/ncb3075
  8.  “EULAR: JAK Inhibitor Effective in RA But Safety Worries Remain”. MedPage Today. June 2009. Retrieved 9 February 2011.
  9.  Clinical trial number NCT00413699 for “Long-Term Effectiveness And Safety Of CP-690,550 For The Treatment Of Rheumatoid Arthritis” at ClinicalTrials.gov
  10.  Matthew Herper. “Pfizer’s Key Drug Walks A Tightrope”. Forbes.
  11.  “Two Phase III Studies Confirm Benefits of Pfizer’s Tofacitinib Against Active RA”. 28 Apr 2011.
  12.  “FDA approves Xeljanz for rheumatoid arthritis”. 6 Nov 2012.
  13.  “Hairless man grows full head of hair in yale arthritis drug trial”. 19 Jun 2014.
  14.  https://clinicaltrials.gov/ct2/show/NCT01465763?term=A3921094&rank=1
  15. “This Drug Brought Pigment Back for Woman with Vitiligo”. TIME. June 27, 2015. Retrieved June 29, 2015.
  16. Nordqvist, Christian (27 April 2013). “Pfizer’s Arthritis Drug Xeljanz (tofacitinib) Receives A Negative Opinion In Europe”. Medical News Today. Retrieved 2 August 2013.
  17. “”XALEJANZ PRESCRIBING INFORMATION @ Labeling.Pfizer.com””.

SEE………http://orgspectroscopyint.blogspot.in/2014/12/tofacitinib-citrate.html

Tofacitinib
Tofacitinib2DACS.svg
Systematic (IUPAC) name
3-[(3R,4R)-4-methyl-3-[methyl(7H-pyrrolo[2,3-d]pyrimidin-4-yl)amino]piperidin-1-yl]-3-oxopropanenitrile
Clinical data
Trade names Xeljanz, Jakvinus
AHFS/Drugs.com entry
Licence data US FDA:link
Pregnancy category
  • US: C (Risk not ruled out)
Legal status
Routes of administration Oral
Pharmacokinetic data
Bioavailability 74%
Protein binding 40%
Metabolism Hepatic (via CYP3A4 andCYP2C19)
Biological half-life 3 hours
Excretion Urine
Identifiers
CAS Registry Number 477600-75-2
ATC code L04AA29
PubChem CID: 9926791
IUPHAR/BPS 5677
DrugBank DB08183
ChemSpider 8102425
UNII 87LA6FU830
ChEBI CHEBI:71200 Yes
ChEMBL CHEMBL221959
Synonyms CP-690550
Chemical data
Formula C16H20N6O
Molecular mass 312.369 g/mol

सुकून उतना ही देना प्रभू, जितने से जिंदगी चल जाये।औकात बस इतनी देना,कि औरों का भला हो जाये।………..P.S. : The views expressed are my personal and in no-way suggest the views of the professional body or the company that I represent.

 

 

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9-(5-oxotetrahydrofuran-2-yl)nonanoic acid methyl ester


9-(5-Oxotetrahydrofuran-2-yl)nonanoic acid methyl ester

353
Name 9-(5-Oxotetrahydrofuran-2-yl)nonanoic acid methyl ester
Synonyms
Name in Chemical Abstracts 2-Furannonanoic acid, tetrahydro-5-oxo-, methyl ester
CAS No 22623-86-5
Molecular formula C14H24O4
Molecular mass 256.35
SMILES code O=C1OC(CC1)CCCCCCCCC(=O)OC

1H NMR

1H NMR

1H-NMR: 9-(5-Oxotetrahydrofuran-2-yl)nonanoic acid methyl ester
500 MHz, CDCl3
delta [ppm] mult. atoms assignment
1.24-1.45 m 10 H 4-H, 5-H, 6-H, 7-H, 8-H
1.57 m 2 H 3-H
1.70 m 1 H 9-H
1.82 m 1 H 9-H
2.27 t 2 H 2-H
2.30 m 2 H 3-H (ring)
2.50 m 2 H 4-H (ring)
3.67 s 3 H O-CH3
4.48 m 1 H 2-H (ring)

NMR XXX

13C NMR

13C NMR

13C-NMR: 9-(5-Oxotetrahydrofuran-2-yl)nonanoic acid methyl ester
125.7 MHz, CDCl3
delta [ppm] assignment
24.9 C3
25.2 C9
28.0-29.2 C4, C5, C6, C7, C8, C3 (ring)
34.0 C2
35.5 C4 (ring)
51.4 O-CH3
81.0 C2 (ring)
174.2 C1 (O-C(=O)-)
177.2 C5 (O-C(=O)-, ring)
76.5-77.5 CDCl3

13C XXX

IR

IR

IR: 9-(5-Oxotetrahydrofuran-2-yl)nonanoic acid methyl ester
[Film, T%, cm-1]
[cm-1] assignment
2931, 2856 aliph. C-H valence
1776 C=O valence, lactone
1737 C=O valence, ester
Cu
10-Undecenoic acid methyl esterIodoacetic acid ethyl esterreacts to9-(5-Oxotetrahydrofuran-2-yl)nonanoic acid methyl esterIodoethane

Synthesis of 9-(5-oxotetrahydrofuran-2-yl)nonanoic acid methyl ester

Reaction type: addition to alkenes, radical reaction, ring closure reaction
Substance classes: alkene, halogencarboxylic acid ester, lactone
Techniques: working with cover gas, stirring with magnetic stir bar, heating under reflux, evaporating with rotary evaporator, filtering, recrystallizing, heating with oil bath
Degree of difficulty: Easy

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Operating scheme

Operating schemeInstructions

http://www.oc-praktikum.de/nop/en/instructions/pdf/4005_en.pdf

Instruction (batch scale 100 mmol)

Equipment 250 mL two-neck flask, protective gas supply, reflux condenser, heatable magnetic stirrer, magnetic stir bar, rotary evaporator, Buechner funnel, suction flask, desiccator, oil bath Substances undecenoic acid methyl ester (bp 248 °C) 19.8 g (22.3 mL, 100 mmol) iodoacetic acid ethyl ester (bp 73-74 °C/ 21 hPa) 27.8 g (15.4 mL, 130 mmol) copper powder (finely powdered, >230 mesh ASTM) 30.5 g (480 mmol) tert-butyl methyl ether (bp 55 °C) 130 mL petroleum ether (bp 60-80 °C) 300 mL Reaction In a 250 mL two-neck flask with magnetic stir bar and a reflux condenser connected with a protective gas piping 19.8 g (22.3 mL, 100 mmol) undecenoic acid methyl ester and 27.8 g (15.4 mL, 130 mmol) iodoacetic acid ethyl ester are mixed with 30.5 g (480 mmol) copper powder under a protective gas atmosphere. Afterwards the reaction mixture is stirred at 130 °C oil bath temperature under protective gas for 4 hours. (Reaction monitoring see Analytics.)

Work up The reaction mixture is cooled down to room temperature, 30 mL tert-butyl methyl ether are added, the mixture is stirred for 5 minutes and filtered off. The copper powder on the filter is washed four times with 25 mL tert-butyl methyl ether each. Filtrates and wash solutions are combined, the solvent is evaporated at the rotary evaporator. A yellow oil remains as crude product. Crude yield: 25.4 g.

The crude product is dissolved in 300 mL petroleum ether under reflux. The solution is allowed to cool down to room temperature, then it is stored in the refrigerator over night for complete crystallization. The crystalline product is sucked off over a Buechner funnel and dried in the vacuum desiccator. The mother liquor is stored again in the refrigerator for a check of complete crystallization. Yield: 19.5 g (76.1 mmol, 76%); white solid, mp 34 °C Comments In order to achieve a quantitative reaction within 4 hours, a fivefold excess of copper is used.

Waste management Recycling The copper powder can be used three times.

Waste disposal Waste Disposal evaporated tert-butyl methyl ether (might contain iodoethane) organic solvents, containing halogen mother liquor from recrystallization organic solvents, containing halogen copper powder solid waste, free from mercury, containing heavy metals

Time 6-7 hours

Break After heating and before recrystallizing

Degree of difficulty Easy

Analytics Reaction monitoring with TLC Sample preparation: Using a Pasteur pipette, two drops of the reaction mixture are taken and diluted with 0.5 mL diethyl ether. TLC-conditions: adsorbant: TLC-aluminium foil (silica gel 60) eluent: petroleum ether (60/80) : acetic acid ethyl ester = 7 : 3 visualisation: The TLC-aluminium foil is dipped in 2 N H2SO4 and then dried with a hot air dryer. Reaction monitoring with GC Sample preparation: Using a Pasteur pipette, one drop of the reaction mixture is taken and diluted with 10 mL dichloromethane. From this solution, 0.2 µL are injected. 10 mg from the solid product are dissolved in 10 mL dichloromethane. From this solution, 0.2 µL are injected. GC-conditions: column: DB-1, 28 m, internal diameter 0.32 mm, film 0.25 µm inlet: on-column-injection carrier gas: hydrogen (40 cm/s) oven: 90 °C (5 min), 10 °C/min to 240 °C (40 min) detector: FID, 270 °C Percent concentration was calculated from peak areas.

Chromatogram

crude product chromatogram

GC: crude product
column DB-1, L=28 m, d=0.32 mm, film=0.25 µm
inlet on column injection, 0.2 µL
carrier gas H2, 40 cm/s
oven 90°C (5 min), 10°C/min –> 240°C (40 min)
detector FID, 270°C
integration percent concentration calculated from relative peak area

pure product chromatogram

GC: pure product
column DB-1, L=28 m, d=0.32 mm, film=0.25 µm
inlet on column injection, 0.2 µL
carrier gas H2, 40 cm/s
oven 90°C (5 min), 10°C/min –> 240°C (40 min)
detector FID, 270°C
integration percent concentration calculated from relative peak area

Substances required

Batch scale: 0.01 mol 0.1 mol 10-Undecenoic acid methyl ester
Educts Amount Risk Safety
10-Undecenoic acid methyl ester
19.8 g H- EUH- P-
Iodoacetic acid ethyl ester
GHS06 GHS05 Danger
27.8 g H300 H314 EUH- P264 P280 P305 + 351 + 338 P310
Reagents Amount Risk Safety
Copper powder
GHS09 Warning
30.5 g H400 EUH- P273
Solvents Amount Risk Safety
tert-Butyl methyl ether
GHS02 GHS07 Danger
130 mL H225 H315 P210
Petroleum ether (60-80)
GHS02 GHS08 GHS07 GHS09 Danger
300 mL H225 H304 H315 H336 H411 EUH- P210 P261 P273 P301 + 310 P331
Others Amount Risk Safety
Sulfuric acid 2N
GHS05 Danger
H314 H290 EUH- P280 P301 + 330 + 331 P305 + 351 + 338 P309 + 310
Solvents for analysis Amount Risk Safety
Petroleum ether (60-80)
GHS02 GHS08 GHS07 GHS09 Danger
H225 H304 H315 H336 H411 EUH- P210 P261 P273 P301 + 310 P331
Acetic acid ethyl ester
GHS02 GHS07 Danger
H225 H319 H336 EUH066 P210 P261 P305 + 351 + 338
Dichloromethane
GHS08 GHS07 Warning
H351 H315 H319 H335 H336 H373 P261 P281 P305 + 351 + 338

Substances produced

Batch scale: 0.01 mol 0.1 mol 10-Undecenoic acid methyl ester
Products Amount Risk Safety
9-(5-Oxotetrahydrofuran-2-yl)nonanoic acid methyl ester

Equipment

Batch scale: 0.01 mol 0.1 mol 10-Undecenoic acid methyl ester
two-necked flask 250 mL two-necked flask 250 mL protective gas piping protective gas piping
reflux condenser reflux condenser heatable magnetic stirrer with magnetic stir bar heatable magnetic stirrer with magnetic stir bar
rotary evaporator rotary evaporator suction filter suction filter
suction flask suction flask exsiccator with drying agent exsiccator with drying agent
oil bath oil bath

Simple evaluation indices

Batch scale: 0.01 mol 0.1 mol 10-Undecenoic acid methyl ester
Atom economy 53.9 %
Yield 76 %
Target product mass 19.5 g
Sum of input masses 370 g
Mass efficiency 53 mg/g
Mass index 19 g input / g product
E factor 18 g waste / g product

………………

………

Total synthesis of the proposed structure of Astakolactin……….Dr Corey Johnson


picture credit…………Dr Corey johnson

Astakolactin is a sesterpene from the Ionian Sea near Greece possessing considerable biological properties. Hence, that’s why the authors decided to synthesize it, and also why the we’re all interested in its structure. In the conclusion of this paper, no biological studies were performed, but the characterization matches that of the natural product, which is a big deal.

read at

http://chemistrycorey.blogspot.in/2014/11/total-synthesis-of-proposed-structure.html

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