Enantioselective Henry reaction catalyzed by copper(II)— Cinchona alkaloid complexes

Abstract

An enantioselective Henry reaction was efficiently carried out under mild reaction conditions in the presence of catalytic 9- epi and natural Cinchona alkaloids and copper (II) acetate. The best catalytic performance was observed for native quinine (12 mol %) and Cu(OAc) 2 (10 mol %). Aromatic and aliphatic aldehydes with nitromethane and its α-substituted derivatives provided the corresponding β-nitroalcohols in good to reasonable yields, high syn-diastereoselectivity, and ( S)-enantioselectivity of up to 94% ee.