Asymmetric Formal Synthesis of (-)-Cephalotaxine via Palladium-Catalyzed Enantioselective Tsuji Allylation

Org Lett. 2018 Feb 16;20(4):1050-1053. doi: 10.1021/acs.orglett.7b04008. Epub 2018 Feb 5.

Abstract

Asymmetric synthesis of the pentacyclic alkaloid (-)-cephalotaxine was accomplished via palladium-catalyzed enantioselective Tsuji allylation for construction of the aza-containing tetrasubstituted stereogenic center (95% yield, 93% ee). The allyl enol carbonate precursor was prepared from Hanaoka's ketone intermediate, which was formed by a novel formic acid promoted ring-expansion reaction.

Publication types

  • Research Support, Non-U.S. Gov't