AN IMPROVED PROCESS FOR THE PREPARATION OF TERBINAFINE INTERMEDIATE

摘要

This application discloses an improved process for the preparation of N-methyl-N-(1-naphthylmethyl)-6,6-dimethyl-2-hydroxyheptan-4-ynyl-1-amine, a key intermediate used in the synthesis of terbinafine ((E)-N-(6,6-dimethyl-2-hepten-4-ynyl)-N-methyl-1-naphthalenemethanamine). Process is involving converting tertiary-butylacetylene to its Grignard derivative via transmetallation using lower alkylmagnesium halides and treating it with 1-[N-methyl-N-(1-naphtylmethyl)amino]-2,3-epoxypropane at -10 DEG C to -20 DEG C, slowly heating the reaction mass to reflux temperature and quenching of reaction mass with ammonium chloride to give the compound of the formula-I as crystalline solid.