Modular Synthesis of α‐Quaternary Chiral β‐Lactams via Three‐Component Asymmetric Kinugasa/Aldol or Kinugasa/Mannich Cascade Reactions

Abstract

The β‐lactam scaffolds are the prevalent structural units in antibiotics and natural products. Herein, three‐component asymmetric Kinugasa/aldol and Kinugasa/Mannich cascade reactions have been developed for constructing α‐quaternary chiral β‐lactams. This strategy enables sequential assembly of alkynes, nitrones and aldehydes (or imines) and creates three contiguous stereogenic centers, controlled by copper(I) catalysts and chiral bis(oxazolidine) ligands. The developed protocol features high enantioselectivity, good reaction efficiency, and mild operational conditions representing a practical and sustainable synthetic tool for the construction of functionalized chiral β‐lactams.