Epimerization methodologies for recovering stereoisomers in high yield and purity

摘要

The present invention relates to methods of subjecting a mixture of stereoisomers to epimerization and optionally recrystallization procedures to obtain a desired stereoisomer in high yield and purity. Relying upon solubility differences, the epimerization desirably is carried out in a solvent mixture that extends the epimerization equilibrium in favor of the desired stereoisomer. Recrystallization from a solvent mixture upgrades the purity even more. Purified stereoisomers are useful in many applications such as intermediates in the synthesis of pharmacologically important molecules.