Hoechst Celanese Corporation

Other

John R Fritch

Apurba Bhattacharya

Carl David Murphy

Larry D Zeagler

Werner H Mueller

Frank B Gupton

John C Saukaitis

Varadaraj Elango

Theodore Horlenko

Donald R Larkin

Michael P Bodman

Carina A McAdams

Olan S Fruchey

Charles B Hilton

Daniel A Aguilar

Carina Araullo-McAdams

O Stanley Fruchey

Phillip S Snyder

William J Seeliger

The present invention pertains to a method of preparing substituted and unsubstituted N-hydroxy-2-aminobutane diacid derivatives which can be dehydrated to 2-aminobut-2-ene dioic acid derivatives, which can be subsequently converted to pyridine and quinoline derivatives.

Process for preparing pyridine and quinoline derivatives

A process is provided whereby S(+)-ibuprofen or R(-)-ibuprofen L-lysinate salt is produced by selective precipitation from a mixture containing enantiomers of ibuprofen and L-lysine. The quantity of L-lysine is not more than about a molar equivalent of the quantity of one of the enantiomers in the ibuprofen enantiomeric mixture. Upon precipitation of one ibuprofen enantiomer from the mixture, the overall precipitate and reaction mixture can be held for a sufficient period of time at a second temperature to allow the first precipitate to redissolve into the reaction mixture and the other ibuprofen enantiomer to precipitate out of the mixture in the salt form. Optically active ibuprofen is racemized by being heated at 100.degree. C. to 300.degree. C. in the substantial absence of other materials.

Selective precipitation of .alpha.-aryl carboxylic acid salts

In a preferred embodiment, an elongated landscape edging strip formed of flexible material has a substantially flat planar bottom support surface and comprises an upstanding, laterally reinforced retainer portion of channel-shaped cross section intermediate and integrally extruded with a flat flexible mowing strip and a flat flexible anchoring strip. The retainer portion, mowing strip, and anchoring strip are secured in conformity to the ground contour along a landscape border. In preferred embodiments, the retainer portion abuts a fence or retains landscape fill on landscaping sheet having an edge secured underneath the landscaping edging strip.

Landscape edging apparatus and method

There is disclosed and claimed a process whereby S(+)-ibuprofen L-lysinate salt is produced by selective precipitation from a mixture containing enantiomers of ibuprofen and L-lysine. The quantity of L-lysine is not more than about a molar equivalent of the quantity of S(+)-ibuprofen in the ibuprofen enantiomeric mixture. The mother liquors after separating the above salt are enriched in R-ibuprofen which is racemized by a novel thermal racemization process and may then be recycled.

Racemization of an enantomerically enriched .alpha.-aryl carboxylic acid

The present invention pertains to a method of preparing substituted and unsubstituted N-hydroxy-2-aminobutane diacid derivatives. The invention also pertains to the use of N-hydroxy-2-aminoethane derivatives (including the N-hydroxy-2-aminobutane diacid derivatives) in the preparation of pyridine derivatives.

Process for preparing pyridinecarboxylic acid derivatives

An elongated landscape edging strip formed of flexible material comprises an upstanding retainer portion intermediate and integral with a thin gauge, readily deformable mowing strip and a thin gauge, readily deformable anchoring strip. The mowing strip and anchoring strip are both secured in conformity to the ground contour along the edge of a mowed area to separate the mowed area from an unmowed area. In a preferred embodiment, the retainer portion has a channel-shaped cross section.

N-acetyl-para-aminophenol is prepared by contacting 4-hydroxyacetophenone oxime with a Beckmann rearrangement catalyst in an alkyl alkanoate reaction solvent. An integrated process is disclosed wherein 4-hydroxyacetophenone is reacted with a hydroxylamine salt and a base to obtain 4-hydroxyacetophenone oxime, the oxime product is extracted from the resulting reaction mixture with a substantially water-immiscible solvent, and the mixture of oxime and substantially water-immiscible solvent is contacted with a Beckmann rearrangement catalyst to produce N-acetyl-para-aminophenol. Novel Beckamnn rearrangement catalysts are used to limit by-product formation in the ester solvent.

Production of acetaminophen

N-acetyl-para-aminophenol is prepared by subjecting 4-hydroxyacetophenone oxime to a Beckmann rearrangement in the presence of a thionyl chloride catalyst and an alkyl alkanoate as the reaction solvent. An integrated process is disclosed wherein 4-hydroxyacetophenone is reacted with a hydroxyl amine salt and a base to obtain the ketoxime of the ketone, e.g., 4-hydroxyacetophenone oxime, extracting the ketoxime product from the reaction with alkanoate ester and subjecting the ketoxime dissolved in the ester to a Beckmann rearrangement in the presence of a thionyl chloride catalyst.

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Corpus Christi, TX, United States of America

John R Fritch