Direct Functionalization of Azepane via Azomethine Ylides: A Highly Efficient Synthesis of Spirooxindoles Bearing a 1‐Azabicyclo[5.3.0]decane Moiety

Spirooxindoles bearing a 1-azabicyclo[5.3.0]decane moiety were synthesized in one step via direct functionalization of the azepane without a transition metal or oxidants. This is an efficient process for the synthesis of fused 7/5-heterobicyclic systems in one step. Furthermore, cycloaddition of the in situ generated azomethine ylide only proceeded for alkenyl sulfone dipolarophiles.