N-Heterocyclic Carbene Catalyzed Ring Expansion of 4-Formyl-β-lactams: Synthesis of Succinimide Derivatives
摘要:
N-Heterocyclic carbene (NHC) has been employed as an efficient catalyst for ring expansion of 4-formyl-beta-lactams, allowing the facile synthesis of succinimide derivatives. This organocatalytic process features readily availability of the catalyst, low catalyst loading, and mild reaction conditions.
An efficient synthesis of optically pure cis-4-formyl-β-lactams (up to 99% ee) by a chiral NHC-catalyzed ring expansion reaction has been realized, featuring the ready availability of both the substrate and the catalyst, and the mild reaction conditions. The current method is also suitable for the synthesis of enantioenriched 4-formyl-β-lactams and succinimides containing quaternary carbon centers