Rapid Synthesis of Bicyclic N‐Heterocyclic Cores from N‐Terminal α,β‐Unsaturated Diazoketones

A method for the synthesis of bicyclic N‐heterocyclic cores from N‐terminal α,β‐unsaturated diazoketones has been developed. The transformation involves three sequential steps that include N ‐deprotection, an intramolecular aza‐Michael, and a photochemical Wolff rearrangement as a one‐pot protocol. By using this strategy, a series of substituted bicyclic N‐heterocycles, particularly, indolizidines and pyrrolizidines, were synthesize in good yields.