Diphenylprolinol Silyl Ether Catalyzed Asymmetric Formal Carbo [3+3] Cycloaddition Reaction of Isopropylidenemalononitrile and α,β‐Unsaturated Aldehyde

Abstract Enantioselective formal carbo [3+3] cycloaddition reaction of isopropylidenemalononitrile ( 1 ) and α,β‐unsaturated aldehyde, catalyzed by diphenylprolinol silyl ether, was developed. The reaction is a domino Michael/aldol‐type reaction, followed by Al 2 O 3 ‐mediated dehydration to afford 5‐substituted cyclohexene derivatives possessing a methylene‐malononitrile moiety, with excellent enantioselectivity.