PRODUCTION OF OPTICALLY ACTIVE N-PROTECTED-N-METHYL- PHENYLALANINE DERIVATIVE

摘要

PROBLEM TO BE SOLVED: To provide a process for producing an optically active N-protected-N- methyl-4-halogenophenylalanine having high purity and useful as a production intermediate for pharmaceuticals on an industrial scale in high efficiency. SOLUTION: A highly purified optically active N-protected-N-methyl-4- halogenophenylalanine (or its salt) is produced from a crude optically active N-protected-N-methyl-4-halogenophenylalanine containing at least its optical isomer as an impurity through a step of the precipitation and separation of the compound in the form of a salt (e.g. DCHA salt). Since the objective compound can be produced in high purity and yield by this process, the process is extremely useful for the production of a production intermediate for pharmaceuticals.