Precipitation-induced asymmetric transformation of chiral alpha-amino acids and salts thereof.

摘要

The present invention provides a method for resolving a mixture of optically active isomers of an alpha -amino acid to obtain the preferred optically active isomer. The mixture of isomers is contacted with at least one chiral resolving agent in an organic acid, which is at least a partial solvent for the alpha -amino acid, and in the presence of a mineral acid, which is present in a quantity which does not protonate the NH2 functionality of the alpha -amino acid to an extent that diastereomer interconversion is substantially prevented, and in the presence of a catalytic amount of an aromatic aldehyde. The contacting results in simultaneous resolution of a desired diastereomer and interconversion of the remaining undesired diastereomer, to provide a very high yield of the desired diastereomer having a very high optical purity. <IMAGE>