A Simple N-Heterocyclic Carbene for the Catalytic Up-conversion of Aldehydes into Stoichiometric Super Electron Donors

Catalytic amounts of 1,3-di(methyl)imidazol-2-ylidene, one of the simplest and most prototypical N-heterocyclic carbene can up-convert aldehydes into powerful stoichiometric sources of electrons (Super Electron Donors) for reductive transformations of iodoaryls (Ered < -2 V). In particular, the hydroarylation of 1,1’-diarylethylenes, which may require high temperatures and inherently generates stoichiometric amounts of oxidised wastes, was performed at room temperature, with the concomitant formation of esters as oxidated co-products.