N-heterocyclic phosphines: Promising catalysts for transfer hydrogenation
Hydride transfer is a prevailing protocol for reduction of unsaturated compounds, which is traditionally accomplished under the catalysis of transition-metals, particularly those of noble metals. Because of concerns associated with their low abundance, high toxicity and harmful transition-metal residues, considerable research has recently focused on the use of main-group organic counterparts as surrogates for conventional metal hydrides.