Efficient and Single Pot Process for the Preparation of Enantiomerically Pure Solifenacin Succinate, an Antimuscarinic Agent.

The development of an efficient and economic one-pot process, in which the configuration of the chiral centers of the starting materials is retained, for the prepa- ration of highly pure solifenacin succinate, an antimu- scarinic agent, is presented in this communication. The earlier reported processes suffer from the drawbacks of racemization and low yields due to the use of strong base, higher temperatures, and longer reaction times. The present work circumvents these issues by activating (3R)-quinu- clidin-3-ol into a mixed active carbonate derivative by treating it with bis(4-nitrophenyl)carbonate. The sub- sequent reaction of the active carbonate with an enantiomerically pure amine without using any base at ambient temperature provided enantiomerically pure soli- fenacin with an overall yield of 90%.