Light-Stable Silver N-Heterocyclic Carbene Catalysts for the Alkynylation of Ketones in Air

摘要

N-Heterocyclic carbene (NHC) silver(I) complexes were employed efficiently in the alkynylation of ketones. These cationic complexes were highly active and efficient under mild conditions and in air without the need for an additive. The mechanism of this transformation was investigated. Experiments suggest that the formation of a silver acetylide key intermediate and the release of one ligand from the silver centre enable the transformation.