Aerojet-general Corporation

Ampac Fine Chemicals LLC

Omnova Solutions Inc.

Aerojet Fine Chemicals LLC

Other

Fluorochem, Inc.

Gencorp, Inc.

Pharmachem Technologies Limited

Aslam A Malik

Thomas G Archibald

Roland P Carlson

Hasan Palandoken

Joy A Stringer

Gerald E Manser

Raymond J Weinert

Guillermina C Garcia

Robert E Medsker

John M Leach

Robert G Miotke

Edward N Kresge

Kenneth Joseph Wynne

Kurt Baum

James Robinson

Todd E Clement

Olivier Dapremont

Der-Shing Huang

Gary L Jialanella

Ali Suleman

Francis Hempenstall

Nicholas Duda

Russell A Livigni

Eugene Bell

Earl G Melby

Charles M Kausch

I Glen Hargis

Francis J Vitus

James E Robbins

Marvin F Young

Donald Dongjaw Tzeng

Boris D Nahlovsky

George R Gettys

Roland P Carson

DerShing Huang

Antonio Romero

Benjamin Mendoza

Novel methods and systems for producing a substantially pure d-threo stereoisomer of methylphenidate or a salt thereof are provided. In particular, methods and systems for producing d-threo-methylphenidate hydrochloride in pure stereoisomeric form from d-threo-ritalinic acid hydrochloride using diazomethane are described. The described methods can be performed on a large scale, and thus provide d-threo methylphenidate or a salt thereof, and particularly the hydrochloride salt of d-threo-methylphenidate, in stereoisomerically pure form and in large quantities from a single batch reaction. Also described are novel compositions of d-threo methylphenidate hydrochloride.

Methods for preparing d-threo-methylphenidate using diazomethane, and compositions thereof

Methods for preparing D-threo methylphenidate using diazomethane, and compositions thereof

The present invention provides a new process for the preparation of 2R,3S-N-isobutyl-N-(2-hydroxy-3-amino-4-phenylbutyl)-p-nitrobenzenesulfonylamide hydrochloride, wherein this compound is prepared directly from the chloromethylalcohol. Importantly, the process of the present invention results in higher yields of 2R,3S-N-isobutyl-N-(2-hydroxy-3-amino-4-phenylbutyl)-p-nitrobenzenesulfonylamide hydrochloride without sacrificing its purity. The processes of the present invention can be used to prepare not only the 2R,3S-derivative, but also the 2S,3S-, 2S,2R- and the 2R,3R-derivatives.

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Product yields in chemical reactions that produce a solid product from a liquid reaction mixture are improved by chromatographically separating certain key impurities from the product mixture prior to crystallization, or from the filtrate after crystallization in which case further product is crystallized from the filtrate. The removal of key impurities either before the first crystallization or between the first and second crystallizations facilitates the crystallization of product to produce a higher yield of product.

Reaction systems with incorporated chromatography units for enhanced product recovery

The present invention provides compounds and methods that can be used to convert 1,2,4-triazole-3-carboxamides to the corresponding 3-cyano-1,2,4-triazoles reliably in one step, with high yields and without the need for elaborate purification.

Process for the preparation of 3-cyano-1,2,4-triazoles

The present invention provides compounds and methods that can be used to convert the intermediate halomethyl ketones (HMKs), e.g., chloromethyl ketones, to the corresponding S,S- and R,S-diastereomers. More particularly, the present invention provides: (1) reduction methods; (2) inversion methods; and (3) methods involving the epoxidation of alkenes. Using the various methods of the present invention, the R,S-epoxide and the intermediary compounds can be prepared reliably, in high yields and in high purity.

Clean, high-yield preparation of S,S and R,S amino acid isosteres

The present invention provides a new process for the preparation of 2R,3S-N-isobutyl-N-(2-hydroxy-3-amino-4-phenylbuty1)-p-nitrobenzenesulfonylamide hydrochloride, wherein this compound is prepared directly from the chloromethylalcohol. Importantly, the process of the present invention results in higher yields of 2R,3S-N-isobutyl-N-(2-hydroxy-3-amino-4-phenylbutyl)-p-nitrobenzenesulfonylamide hydrochloride without sacrificing its purity. The processes of the present invention can be used to prepare not only the 2R,3S-derivative, but also the 2S,3S-, 2S,2R- and the 2R,3R-derivatives.

Preparation of 2R,3S-N-isobutyl-N-(2-hydroxy-3-amino-4-phenylbutyl)-P-nitrobenzenesulfonylamide hydrochloride and other derivatives of 2-hydroxy-1,3-diamines

A halide salt of a 1-(hydroxyiminomethyl-1-pyridino)-3-(halomethyl)-2-oxapropane is prepared by adding a pyridinealdoxime to a bis-halomethylether in such a manner that the bis-halomethylether is maintained in excess throughout the addition. This procedure produces the halide salt of a 1-(hydroxyiminomethyl-1-pyridino)-3-(halomethyl) -2-oxapropanein high yield and purity, which facilitates its use as an intermediate in the manufacture of an asymmetrically substituted 1,3-di (1-pyridino)-2-oxapropane, a class of compounds that are generally useful antidotes to various toxic agents. A prominent member of the class is the dimethylsulfonate salt of 1-(2-hydroxyiminomethyl-1-pyridino)-3 -(4-carbamoyl-1-pyridino)-2-oxapropane. The use of mercaptoalkyl-functionalized polymers is disclosed as a preferred metal ion scavenger for a final purification step in the manufacture of these compounds.

Process for halomethyl ethers of hydroxyiminomethyl quaternary pyridinium salts

The present invention provides a new process for the preparation of 2S,3S-N-isobutyl-N-(2-hydroxy-3-amino-4-phenylbutyl)-p-nitrobenzenesulfonylamide hydrochloride, wherein this compound is prepared directly from the chloromethylalcohol. Importantly, the process of the present invention results in higher yields of 2S,3S-N-isobutyl-N-(2-hydroxy-3-amino-4-phenylbutyl)-p-nitrobenzenesulfonylamide hydrochloride without sacrificing its purity. The processes of the present invention can be used to prepare not only the 2S,3S-derivative, but also the 2R,3S-, 2S,2R- and the 2R,3R-derivatives.

This application is directed to novel fluorinated polymers and prepolymers derived from mono-substituted oxetane monomers having fluorinated alkoxymethylene side-chains and the method of making these compositions. The mono-substituted fluorinated oxetane monomers having fluorinated alkoxymethylene side-chains are prepared in high yield by the reaction of a fluorinated alkoxides with either 3-halomethyl-3-methyloxetane premonomers or aryl sulfonate derivative of 3-hydroxymethyl-3-methyloxetane premonomers. Preparation of a mono-substituted 3-bromomethyl-3-methyloxetane premonomer via a simple, high yield process amenable to commercial scaleup is also disclosed. The fluorinated oxetane monomers of this invention can be readily homo/co-polymerized in the presence of a Lewis acid and polyhydroxy compounds to obtain hydroxy-terminated polyether prepolymers having fluorinated alkoxymethylene side chains. Additionally, the fluorinated oxetane monomers can be copolymerized with non-fluorinated monomers such as tetrahydrofuran to give polyether prepolymers with improved hydrocarbon compatibility. These prepolymers are polydisperse and exhibit number average molecular weights from 5,000 to about 50,000. These prepolymers are amorphous oils with primary hydroxy end-groups and thus function efficiently as the soft block for the synthesis of a variety of thermoset/thermoplastic elastomers and plastics having the characteristics of very low surface energy, high hydrophobicity, low glasss transition temperature and low coefficient of friction. The polyurethanes derived from the prepolymers of this invention are elastomeric and, in addition to the above characteristics, exhibit high moisture resistance, high tear strength and excellent adhesion to a variety of substrates.

Fluorinated thermoset polyurethane elastomers prepared from polyether prepolymers formed from mono-substituted fluorinated oxetane monomers

The present invention provides compounds and methods that can be used to convert the intermmediate halomethyl ketones (HMKs), e.g., chloromethyl ketones, to the corresponding S,S- and R,S-diastereomers. More particularly, the present invention provides: (1) reduction methods; (2) inversion methods; and (3) methods involving the epoxidation of alkenes. Using the various methods of the present invention, the R,S-epoxide and the intermediary compounds can be prepared reliably, in high yields and in high purity.

Clean, High-yield preparation of S,S and R,S amino acid isosteres

This invention is directed to mono- and bis-substituted oxetane monomers having fluorinated alkoxymethylene side chains, hydroxy-terminated prepolymers derived from these mono- and bis-substituted oxetane monomers and tetrahydrofuran (THF), and polymers produced from these prepolymers, as well as the synthesis processes associated with each, and the use of the monomers, prepolymers and ultimate polymers, both directly and as components of numerous compositions.

Amorphous polyether glycols based on bis-substituted oxetane monomers

Amorphous polyether glycols based on bis-substituted oxetane and tetrahydrofuran monomers

Monofunctional polyfluorooxetane oligomers and polymers are prepared by the cationic polymerization of fluorooxetane monomers with a monoalcohol. The fluorooxetane oligomers or polymers can be copolymerized with generally cyclic ethers. Alternatively, the polyfluorooxetane oligomer or polymer having a single hydroxyl end group can be functionalized with a variety of compounds so as to yield a functional end group such as an acrylate, a methacrylate, an allylic, an amine, etc., with the functionalized oligomer or polymer being suitable for use in radiation curable or thermal curable coating compositions. These functionalized polymers can be copolymerized and cured to provide improvements in wetting and surface properties that have previously been provided by migratory chemicals such as waxes and oils. The partially or fully fluorinated side groups of the fluorooxetanes are believed to be disproportionately present at the interfaces between the coating and the substrate and between the coating and the atmosphere.

Monohydric polyfluorooxetane polymer and radiation curable coatings containing a monofunctional polyfluorooxetane polymer

The present invention provides, inter alia, a novel process for the preparation of Citalopram, a known antidepressant.

Process for the preparation of Citalopram intermediate

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Cameron Park, CA, United States of America

Aslam A Malik