Journal of the American Chemical Society, Vol.140, No.40, 12687-12690, 2018
Enantioselective Oxidative Coupling of Carboxylic Acids to alpha-Branched Aldehydes
A new reactivity in organocatalysis is proposed to account for the coupling of carboxylic acids to alpha-branched aldehydes by combining primary amine catalysis and an oxidant. The developed methodology is an enantioselective alpha-coupling of aromatic and aliphatic carboxylic acids to alpha-branched aldehydes and proceeds in high yields (up to 97%) and for most examples good enantioselectivities (up to 92% ee). On the basis of experimental and mechanistic observations, the role of the primary amine catalyst is discussed.