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AssigneeHoechst Celanese Corporation
InventorsApurba Bhattacharya, John R. Fritch, Carl D. Murphy, Larry D. Zeagler, Carina A. McAdams
Estimating the term…
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.
A process for preparing a first salt of an amino acid and an .alpha.-arylcarboxylic acid of the formula:
A process for preparing a first salt of an amino acid and an .alpha.-arylcarboxylic acid of the formula Ar(R)CHCO.sub.2 H, from a second salt of an anion and a protonated cation of said amino acid, said process comprising:
A process for preparing a salt of an amino acid and an .alpha.-arylcarboxylic acid of the formula Ar(R)CHCO.sub.2 H, said process comprising distilling water from a mixture containing said amino acid and said .alpha.-arylcarboxylic acid and then precipitating said salt from said mixture, wherein R is selected from the group consisting of C.sub.1 -C.sub.8 alkyl and C.sub.1 -C.sub.8 substituted alkyl;
Dependencies are inferred from the claim text.