Crossing the Ring: A Journey of the Nitroso-ene Reaction

Recent progress in the nitroso-ene reaction indicates the potentially rich reactivity of the nitroso species. In this study, we highlight the synthetic efforts towards the construction of the aza-spirocyclic or aza-bridged ring embedded in biologically significant alkaloids via the proposed approach. Our endeavors along this direction are exemplified in the formal synthesis of (±)-cephalotaxine and the total synthesis of (–)-hosieine A. 1 Introduction 2 Aza-Spirocyclane: A Formal Synthesis of (±)-Cephalotaxine 3 Method Development 4 Aza-Bridge Ring: A Total Synthesis of (–)-Hosieine A 5 Epilogue