C5’‐Nitrated Cinchona Catalysts for Asymmetric Michael Addition Reaction

Abstract

C5’‐Nitro‐dihydroquinine (Q1), prepared from dihydroquinine (HQ), exhibited high catalytic activity in an asymmetric Michael reaction. The nitro group at the C5’ position of Q1 was vertically fixed to the quinoline ring, as confirmed by X‐ray crystallography. Q1 exerted a high level of asymmetric induction, superior to that of the non‐nitrated HQ catalyst.