Concise Stereoselective Synthesis of (−)‐Podophyllotoxin by an Intermolecular Iron(III)‐Catalyzed Friedel–Crafts Alkylation

Abstract

Without further ado, the building blocks 1–3 were combined in three CC bond-forming reactions to provide the enantiomerically pure natural product (−)-podophyllotoxin (4). The stereogenic center at C1 was generated in the key reaction, a diastereoselective iron(III)-catalyzed intermolecular Friedel–Crafts alkylation.