Acid‐Catalyzed Carbene Transfer from Diazo Compounds: Carbocation versus Carbene as Key Intermediate

摘要

Abstract An efficient mechanism for the acid‐catalyzed formal carbene transfer from diazo compounds to nucleophilic substrates is disclosed by DFT calculations. In sharp contrast to recent proposal via neutral carbene‐like intermediates, the new mechanism involves selective diazo C‐protonation to form catalytic electrophilic carbocations, thus enabling a broad choice of metal‐free acid catalysts and nucleophilic substrates.