Enantioselective Synthesis of Succinimides by Michael Addition of 1,3-Dicarbonyl Compounds to Maleimides Catalyzed by a Chiral Bis(2-aminobenzimidazole) Organocatalyst

A wide variety of chiral succinimides have been prepared in high yields and enantioselectivities by asymmetric conjugate addition of 1,3‐dicarbonyl compounds to maleimides under very mild reaction conditions using a bifunctional benzimidazole‐derived organocatalyst. Computational and NMR studies support the hydrogen‐bonding activation role of the catalyst and the origin of the stereoselectivity of the process. The chiral 2‐aminobenzimidazole‐derived catalyst 5f serves as very efficient and selective bifunctional organocatalyst in the asymmetric conjugate addition of 1,3‐dicarbonyl compounds to maleimide and N‐substituted maleimides. Computational and NMR studies support the hydrogen‐bonding activation role of the catalyst and the origin of the stereoselectivity of the process.