METHOD FOR MANUFACTURING OPTICALLY ACTIVE 2- METHYLPIPERAZINE

摘要

PROBLEM TO BE SOLVED: To provide a method for manufacturing an optically active 2- methylpiperazine capable of separating both the enantiomers of S-isomer and R-isomer of 2-methylpiperazine by using a single optical resolution agent, and further to provide a method for manufacturing an optically active 2- methylpiperazine capable of manufacturing the optically active 2- methylpiperazine at a higher yield than a conventional method and recovering the used optical resolution agent efficiently. SOLUTION: A method for manufacturing an optically active (S)-(+)- or (R)-(-)-2-methylpiperazine comprises the following steps: one equivalent of racemic 2-methylpiperazine and 2-3 equivalents of optically active 2- phenoxypropionic acid are made to react in a reaction solvent; an optically active 2-methylpiperazine phenoxypropionate of slightly soluble diastereomer salt formed above is separated from the reaction mixture; and the enantiomer of 2-methylpiperazine which is opposite to the enantiomer of 2-methylpiperazine constituting the slightly soluble diastereomer salt is separated from the mother liquid of the above-mentioned separation step.