| 摘要 |
A new process for the optical resolution of racemic mixtures of alpha -naphthylpropionic acids of formula <IMAGE> I wherein R1 is (C1-6) alkyl and R2 represents hydrogen or a halogen atom comprises reacting a racemic mixture of a compound of formula II <IMAGE> II wherein R1 and R2 have the above seen meanings and R3 is a reactive group, with an optically active aminoacid of formula <IMAGE> III wherein R4 represents a (C1-8) alkyl, phenyl, substituted phenyl, benzyl, substituted benzyl or carboxy, and m is an integer from 0 to 4, to give a pair of diastereoisomeric amides of formula <IMAGE> IV wherein R1, R2, R4 and m have the above seen meanings, and M is a hydrogen atom or a cation of an alkali metal or a cation of an organic base. Compounds IV are resolved into the single diastereoisomeric amides d,d or 1,d, or d,1 or 1,1. Acid hydrolysis gives the optically active compound I.
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