NOVEL METHOD FOR PREPARING PREGABALIN

摘要

A method for preparing pregabalin is provided to produce optically pure pregabalin from chiral bicyclic lactone with high yield without requiring a step of removing an undesired R-enantiomer. A method for preparing pregabalin includes the steps of: (i) subjecting a bicyclic lactone compound of the following formula 2 to a cyclopropane ring opening reaction and a decarboxylation reaction by a nucleophilic addition reaction of isopropylcuprate to prepare a lactone compound of the following formula 3; (ii) subjecting the obtained lactone compound to halogenation, azidation, and hydrolysis through a lactone ring opening reaction to prepare a compound of the following formula 4; and (iii) reducing the compound of the formula 4 to prepare the pregabalin of the following formula 1. In the formula 2, R is a C1-6 linear or branched alkyl group.