Ethyl Corporation

Albemarle Corporation

Other

Albermarle Corporation

Thanikavelu Manimaran

Charles H Kolich

W Dirk Klobucar

Richard A Holub

Alvin E Harkins, Jr

G Patrick Stahly

Randall S Barton

Bonnie G McKinnie

Tse-Chong Wu

Hassan Y Elnagar

R Carl Herndon, Jr

Fred J Impastato

Alicia A Potter

James E Torres

Hao V Phan

Felix M Orihuela

Robert E Young

Ronald C Zumstein

Thomas J Callender

Samuel H Dubois

B Gary McKinnie

A process for the production of an aliphatic bromide in which the bromine atom is attached to a terminal carbon atom, which process comprises continuously feeding olefin having a terminal double bond, gaseous hydrogen bromide, and a molecular oxygen-containing gas into a liquid phase reaction medium comprised of aliphatic bromide to cause anti-Markovnikov addition of HBr to terminal olefin, the feeds being proportioned and maintained to provide a molar excess of hydrogen bromide relative to terminal olefin in the range of about 1 to about 5 percent, and a molar ratio of molecular oxygen to terminal olefin of less than 0.005. The process is especially suited for production of n-propyl bromide.

Process for producing n-propyl bromide or other aliphatic bromides

The present invention relates to a method for recovering antimony catalysts wherein the formation of insoluble solids is reduced.

Polymer halogenation process with catalyst recovery

A process for brominating a styrenic polymer in an organic solvent in the presence of an antimony trihalide catalyst such that a reaction mass containing brominated styrenic polymer in an organic phase is formed is improved by mixing hydrochloric acid or hydrobromic acid, or both, with said reaction mass at least once to extract antimony catalyst residues from said reaction mass as an acidic aqueous phase. Preferably, catalyst residues are recovered from the acidic aqueous phase and still more preferably, recovered antimony trihalide catalyst residues are recycled to constitute at least a portion of the antimony trihalide catalyst used in preparing the brominated styrenic polymer.

Recovery of antimony catalyst residues from bromination reaction mixtures

Tetrabromobisphenol-A is produced in a bromination process where no bromine or only a very small proportion of bromine is fed to the reactor. In the process aqueous hydrobromic acid, is the sole source or a major source of the bromine. In the process there are at least three concurrent continuous feeds to the reactor. One is composed of bisphenol-A and/or underbrominated bisphenol-A and a water-miscible organic solvent. The second is gaseous hydrogen bromide or preferably, aqueous hydrobromic acid, and the third is aqueous hydrogen peroxide. Optionally a small additional continuous feed of bromine can be employed. The feeds are proportioned to maintain a liquid phase containing (i) from above about 15 to about 85 wt % water, based upon the amount of water and water-miscible organic solvent in such liquid phase, and (ii) an amount of unreacted bromine that is in excess over the stoichiometric amount theoretically required to convert the bisphenol-A and/or underbrominated bisphenol-A to tetrabromobisphenol-A. The tetrabromobisphenol-A continuously forms as a solids phase in a yield of at least about 90% based on bisphenol-A and/or underbrominated bisphenol-A fed. The reaction mass is agitated and/or refluxed to maintain a substantially uniform slurry in the reactor. An amount of the slurry is continuously removed so that the volume of the contents of the reactor remains substantially constant.

Process for the preparation of tetrabromobisphenol-A

This invention relates, inter alia, to a process for the production of tetrabromobisphenol-A by the bromination of bisphenol-A and/or underbrominated bisphenol-A, which process features: a water and water-miscible organic solvent reaction medium; a relatively high reaction temperature; and the presence, in the reaction medium, of both (i) excess unreacted Br,during the feed of bisphenol-A to the reactor, and (ii) sufficient HBr to protect the tetrabromobisphenol-A produced against undesirable color formation. Tetrabromobisphenol-A precipitates from the reaction mass and is easily recovered. Product of high purity (97% or more) and very low color (APHA of 50 or less) can be produced, even when using large excesses of bromine in the reaction.

This invention relates, inter alia, to a process for the production of tetrabromobisphenol-A by the bromination of bisphenol-A and/or underbrominated bisphenol-A, which process features: a water and water-miscible organic solvent reaction medium; a relatively high reaction temperature; and the presence, in the reaction medium, of both (i) excess unreacted Br,during the feed of bis-phenol-A to the reactor, and (ii) sufficient HBr to protect the tetrabromobisphenol-A produced against undesirable color formation. Tetrabromobisphenol-A precipitates from the reaction mass and is easily recovered. Product of high purity (97% or more) and very low color (APHA of 50 or less) can be produced, even when using large excesses of bromine in the reaction.

Bisphenol-A or preferably, a mixture of bisphenol-A and underbrominated bisphenol-A, is brominated in a liquid phase reaction medium in which tetrabromobisphenol-A is relatively insoluble, using a stoichiometric deficiency of bromine to thereby form in the reaction mass a precipitate (i.e., a solids phase) composed of 50-95 wt % of tetrabromobisphenol-A and 50-5 wt % of underbrominated bisphenol-A. The precipitate is separated from the reaction mass, preferably during the bromination, and tetrabromobisphenol-A is recovered from the precipitate. Preferably underbrominated bisphenol-A is recycled as feed to the bromination. The process technology of this invention has the capability of producing high quality tetrabromobisphenol-A (high purity, good color, low ionic halide content) with efficient raw material utilization, minimized waste product formation, and minimized waste disposal costs.

Process for producing tetrabromobisphenol-A

Optically active carboxylic acids, salts or esters, such as the profen-type compounds, are racemized in the presence by nitrogenous bases such as methylbenzylamine by heating an aqueous solution of such optically active compounds in the presence of a suitable excess of an alkali metal hydroxide relative to the amount optically active carboxylic compound present in the solution. The process not only enables conversion of inactive or undesirable enantiomers of compounds such as naproxen or ibuprofen into a usable, desirable enantiomers in an efficient and economical manner, but avoids conversion of the nitrogenous base into amide. Thus the deleterious consequences of amide formation are avoided.

Racemization process for optically active carboxylic acids or salts or

A process is disclosed for obtaining a compound of the formula

Ultrasonic process

A process for obtaining a substantially pure enantiomer of an hydrocarbyl amine is described. The process utilizes first an enantiomerically enriched mixture the of hydrocarbyl amine obtained from kinetic resolution, diastereomeric crystallization or asymmetric synthesis processes. This enriched mixture is reacted with an inorganic acid producing a salt that has the following properties: 1) has at least one eutectic point; 2) a composition that is not at the eutectic point; and 3) a eutectic composition that is closer to the racemic composition than is the eutectic composition of said hydrocarbyl, or be a solid where the salt is a liquid. A substantially pure, enantiomeric salt is separated, leaving a mother liquor comprising the solvent and the hydrocarbyl amine enriched in the other enantiomer.

Enantiomeric resolution

A process for preparing alkyl esters of ibuprofen is provided. A 1-halo-1-(4-isobutylphenyl)ethane is reacted in an anhydrous medium with carbon monoxide in the presence of an alkoxide source at a temperature between about 10.degree. C. and about 200.degree. C. An excess of several moles of alcohol is preferred. An acid such as hydrogen chloride may also be added. As catalyst, a palladium compound having at least one acid-stable ligand is present; however, an excess of ligand over palladium is advantageous.

Catalytic process for preparing the alkyl esters of ibuprofen

A process for the asymmetric reduction of carboxylic acids of the formula ##STR1## or the amine salts thereof, where R and R.sub.1 are the same or different and are hydrogen, alkyl, cycloalkyl or haloalkyl and Ar is aryl or substituted aryl is disclosed.

Asymmetric hydrogenation of aromatic-substituted olefins using

A process is disclosed that is useful for separating the enantiomers of a racemic mixture of an aliphatic carboxylic acid having the formula ##STR1## where R.sub.1 is hydrogen or alkyl, R.sub.2, R.sub.3 and R.sub.4 are independently different and are hydrogen, alkyl, cycloalkyl, alkenyl, alkynyl, phenyl, substituted phenyl, naphthyl, substituted naphthyl, heteroaryl, substituted heteroaryl, haloalkyl, alkoxyalkyl, alkylthioalkyl, phenylalkyl, substituted phenylalkyl, heteroalkylalkyl, substituted heteroalkylalkyl or cycloalkylalkyl. The process comprises forming a conglomerate salt by reacting the racemic mixture with a base, the conglomerate salt being a mixture of the enantiomeric salts and having the following properties:

Profen resolution

A process for obtaining an aryl-substituted aliphatic nitrile is described. The process utilizes a solution of an aryl-substituted aliphatic halide and an organic or inorganic cyanide substantially insoluble in the solution. The mixture is subjected to ultrasonic vibrations for a time and at a temperature sufficient to produce the aryl-substituted aliphatic nitrile.

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Baton Rouge, LA, United States of America

Thanikavelu Manimaran