Rh-Catalyzed Enantioselective Allylation of N-Tosyl- and N-Nosylaldimines: Total Synthesis of (-)-Crispine A

Org Lett. 2018 Jan 5;20(1):158-161. doi: 10.1021/acs.orglett.7b03523. Epub 2017 Dec 19.

Abstract

The unprecedented development of asymmetric Rh-catalyzed 1,2-allylation of N-Ts- and N-Ns-aldimines is achieved. This protocol utilizes potassium allyltrifluoroborates and various aldimines to generate enantioenriched homoallylic amines in the presence of 3.0 mol % of Rh(I)/L1b catalyst with up to 90% yield, 98% ee (R = H), and 10:1 diastereoselectivity (R = Me or Ph), yielding the same major diastereomer when using potassium (E)- and (Z)-crotyltrifluoroborate. Its synthetic utility is also illustrated in the total synthesis of (-)-crispine A.

Publication types

  • Research Support, Non-U.S. Gov't