Acidic Hydrogen‐Tethered Allylic Carbonates for Phosphine‐Catalyzed (4+2) Annulation of Sulfamate‐Derived Cyclic Imines

Abstract The acidic hydrogen‐tethered allylic carbonates were successfully applied in phosphine catalysis. Their (4+2) annulation reaction with sulfamate‐derived cyclic imines under phosphine catalysis worked well to produce tetrahydropyridine‐fused heterocyclic compounds in high yields. A moderate ee was obtained in the initial screening. The zwitterionic intermediate produced through in‐situ deprotonation functioned as a four‐membered synthon. magnified image