Synthesis of diclofenac.

Abstract

Diclofenac, a potent antiinflammatory agent, was prepared by acid-catalyzed cyclization of N-(2, 6-dichlorophenyl)-α-(methylsulfinyl) acetanilide or of α-chloro-N-(2, 6-dichlorophenyl)-α-(methylthio) acetanilide followed by desulfurization and hydrolysis of the resultant 1-(2, 6-dichlorophenyl)-3-(methylthio) oxindole.