ppm Pd-catalyzed, Cu-free Sonogashira couplings in water using commercially available catalyst precursors

Chem Sci. 2019 Jan 31;10(12):3481-3485. doi: 10.1039/c8sc05618h. eCollection 2019 Mar 28.

Abstract

A new catalyst that derives from commercially available precursors for copper-free, Pd-catalyzed Sonogashira reactions at the sustainable ppm level of precious metal palladium under mild aqueous micellar conditions has been developed. Both the palladium pre-catalyst and ligand are commercially available, bench stable, and highly cost-effective. The catalyst is applicable to both aryl- and heteroaryl-bromides as educts. A wide range of functional groups are tolerated and the aqueous reaction medium can be recycled. An application to a key intermediate associated with an active pharmaceutical ingredient (ponatinib) is discussed.