Experimental investigation of an oxidative C−C coupling reaction catalyzed by HAuCl₄

Reaction monitoring by electrospray (ESI) mass spectrometry (MS) is a valuable technique to investigate reaction mechanisms. It allows glimpse into the reacting solution and characterization of transient intermediates tandem spectrometry. Herein we studied an intriguing gold(III)-catalyzed synthesis dicoumarins which includes combination hydroarylation homocoupling steps. Reactants products could be detected in positive mode. In negative mode, some species corroborating proposed direct infusion ESI solutions. The ions were characterized accurate determinations gas-phase fragmentation. Thus, indications for nature ligand sphere catalytic cycle collected.