Efficient and Chirally Specific Synthesis of Phenanthro‐Indolizidine Alkaloids by Parham‐Type Cycloacylation

A concise, efficient and modular route involving Parham‐type cycloacylation as the key step has been used to synthesize six enantiopure phenanthro‐indolizidine alkaloids 1a – c . The preparation of enantiomerically pure tylophora alkaloids and their seco analogues on a large‐scale is now feasible. The alcohol intermediates 8a – c , which are difficult to prepare by other synthetic methodologies, have been synthesized by a metallation–cyclization–reduction sequence in excellent yields.