Recent Advances in N-Heterocyclic Carbene Coinage Metal Complexes in A3-Coupling and Carboxylation Reaction

Owing of their accessibility and wide range of reactivities, alkynes make for fascinating building blocks. Either a selective alkyne carbon-carbon triple bond reaction or activation of the terminal alkyne C-H bond may be employed to functionalize them. Monocationic coinage metal complexes with a d10 electronic configuration are effective catalysts for alkyne activation. Silver(I) and gold(I) N-heterocyclic (NHC) systems are emerging as promising catalysts in multicomponent alkyne activation reactions; this review paper focuses on A(3) (aldehyde-amine-alkyne)-coupling reaction and carbon dioxide fixation, furnishing a systematic overview of the scientific advances achieved during the last two decades. This study will carefully compare the corresponding silver and gold complexes employed in the two processes. The differences in reaction routes brought about by the catalyst ligand structure will be investigated with an emphasis on evaluating the benefits provided by the easily tuneable NHC backbone, in terms of chemo- and stereo-selectivity.

Automated summary

Due to their accessibility and wide range of reactivities, alkynes are considered fascinating building blocks. Selective alkyne carbon-carbon triple bond reactions or activation of the terminal alkyne C-H bond can be used for functionalization. Monocationic coinage metal complexes with a d10 electronic configuration have been found to be effective catalysts for alkyne activation. Silver(I) and gold(I) N-heterocyclic (NHC) systems are emerging as promising catalysts for multicomponent alkyne activation reactions, particularly in A(3) (aldehyde-amine-alkyne)-coupling and carbon dioxide fixation. This study compares the silver and gold complexes used in these processes and evaluates the benefits provided by the easily tuneable NHC backbone in terms of chemo- and stereo-selectivity.