Concise Synthesis of (±)‐Fortuneicyclidins and (±)‐Cephalotine B Enabled by Pd‐Catalyzed Dearomative Spirocyclization**

Abstract

AbstractTotal syntheses of C11‐oxygenated Cephalotaxus alkaloids, fortuneicyclidins A and B, and cephalotine B, were achieved. The key for the synthesis is a Pd‐catalyzed dearomative spirocyclization of bromofurans with N‐tosylhydrazones, followed by acid‐mediated tandem transformation to construct the tetracyclic skeleton with the C11‐oxygen functional group. Chemo‐selective and catalytic functional group conversions of the tetracyclic intermediate completed the synthesis of fortuneicyclidins and cephalotine B in 8 and 9 steps, respectively.