APPROACH TO PHENANTHROINDOLIZIDINE ALKALOIDS USING ORGANIC AZIDES WITH 1-ARYL ALLYLIC ALCOHOLS: UNEXPECTED TANDEM REACTIONS TO INDENYL AZIRIDINES VIA NAZAROV CYCLIZATION

摘要

Organic azide cyclization reactions with 1-aryl allylic alcohols were investigated in a synthetic study of phenanthroindolizidine alkaloids. Unsaturated imines (enimines) were effectively obtained from the allylic alcohol adjacent to electron-rich aromatic rings under thermal reaction conditions. The tandem aziridination-Nazarov reactions to indenyl aziridines were preferred to the acid-mediated enimine formation via Schmidt reaction in the case of 3-aryl diallylic alcohols.