A highly efficient gold and palladium combined methodology for the Sonogashira coupling
of a wide array of electronically and structurally diverse aryl and heteroaryl halides
is described. The orthogonal reactivity of the two metals shows high selectivity and
extreme functional group tolerance in Sonogashira coupling. A brief mechanistic study
reveals that the gold acetylide intermediate enters into the palladium catalytic cycle
at the transmetalation step.
Key words
gold catalysis - cross-coupling - Sonogashira coupling - gold–palladium combined