Organocatalyst-mediated dehydrogenation of aldehydes to α,β-unsaturated aldehydes, and oxidative and enantioselective reaction of aldehydes and nitromethane catalyzed by diphenylprolinol silyl ether

A one-pot transformation of aldehydes into α,β-unsaturated aldehydes was developed using both N-benzyl-N-methylamine and 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) as catalysts and MnO₂ as a terminal oxidant. An oxidative and enantioselective reaction of aldehydes and nitromethane was established using both diphenylprolinol silyl ether and DDQ as a catalyst with MnO₂ as a terminal oxidant, in which synthetically important β-substituted γ-nitro aldehydes were obtained with excellent enantioselectivity.