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AssigneeRiedel-de Haen Aktiengesellschaft
InventorsHorst Schmand, Wolfgang Dannenberg
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Optically active 2-amino-2-phenylacetic acid of the formula ##STR1## in which R.sub.1, R.sub.2 and R.sub.3, which are identical or different, denote hydrogen, halogen, hydroxy, alkyl, acyl, or alkoxy, is prepared by asymmetrical transformation of a corresponding DL-aminophenylacetonitrile with L(+)-tartaric acid. To this end the corresponding DL-2-amino-2-phenyl-acetonitrile is reacted with approximately equimolar amounts of L(+)-tartaric acid in the presence of at least one alkanol having from 1 to 5 carbon atoms and/or at least one carbonyl compound at a temperature of from 0.degree. to 50.degree. C. and the mixture is stirred for 2 to 120 hours at the indicated temperature. The crystallized transformation product is separated, hydrolyzed by treatment with an acid and the desired product is isolated.
A process for the manufacture of an optically active optionally substituted 2-amino-2-phenylacetic acid of the formula ##STR5## wherein R.sub.1, R.sub.2 and R.sub.3, which are identical or not all the same, are hydrogen, halogen, hydroxy, alkyl, acyl or alkoxy, which consists essentially of reacting a DL-2-amino-2 -phenyl-acetonitrile of the formula ##STR6## with an approximately equimolar amount of L(+)-tartaric acid in the presence of at least one alkanol of from 1 to 5 carbon atoms at a temperature of from 0.degree. to 50.degree. C.;
Dependencies are inferred from the claim text.