IMPROVED PROCESS FOR THE PREPARATION OF ESZOPICLONE

摘要

The present invention relates to an improved process for the preparation of eszopiclone comprising the steps of condensation of 6-(5-chloropyrid-2-yl)-5-hydroxy-7-oxo-5.6-dihydropyrrolo[3,4-b]pyrazine with l-chlorocarbonyl-4-methylpiperazine hydrochloride and then resolution of obtained racemic Zopiclone using D-(+)-dibenzoyl tartaric acid monohydrate; subsequently neutralization of the dibenzoyl tartarate salt provides eszopiclone. The said process is environmentally friendly; high yielding and avoids mixing of solvents.