Sequential and domino Sonogashira coupling: Efficient tools for the synthesis of diarylalkynes

The Sonogashira coupling reaction of aryl halides with a masked acetylene, leading to the formation of diarylethynes is reviewed. The process is either run in a sequential coupling–deprotection–coupling manner, or sometimes it is carried out in one-pot, a reaction we coined domino coupling. The procedures were also extended to the synthesis of compound libraries.