Sonogashira Coupling

Abstract

It is a palladium‐catalyzed noncarbonylative coupling between terminal acetylenes (alkynes) and aryl or vinyl halides in the presence of a copper (I) salt and a large excess of amine (as the solvent or co‐solvent). Therefore, this reaction is generally known as the Sonogashira coupling. Occasionally, this reaction is also referred to as the Sonogashira–Hagihara reaction. The reaction's conditions, mechanistic features and weaknesses of the Sonogashira coupling have been discussed. The most important improvement for the Sonogashira coupling is probably to perform this reaction under copper‐free conditions. This reaction has very broad application in the preparation of alkynes.