Intramolecular 1,3-dipolar cycloaddition as a tool for the preparation of azaspirocyclic keto aziridines. Synthesis of intermediates for the total synthesis of (±) (±)-cephalotaxine

Article abstract of DOI:10.1016/S0040-4039(97)00948-9

The thermal intramolecular azide-enone 1,3-dipolar cycloaddition to azaspirocyclic keto aziridines 17 and 18 is reported. α-Hydroxylation and oxidation to the corresponding diketo aziridine 2 provided an intermediate in a synthetic approach toward cephalo