Asymmetric Total Synthesis of Vincadifformine Enabled by a Thiourea-Phosphonium Salt Catalyzed Mannich-Type Reaction

Chemistry. 2019 May 2;25(25):6306-6310. doi: 10.1002/chem.201900896. Epub 2019 Apr 11.

Abstract

An asymmetric total synthesis of vincadifformine is described. The limited tactics with chiral cation-directed catalysis in total synthesis inspired the development of our strategy for accessing this alkaloid in enantionrich form. The route features a thiourea-phosphonium salt catalyzed Mannich-type reaction, a phosphine-promoted aza-Morita-Baylis-Hillman reaction and a trifluoroacetic acid promoted deprotection/amidation cascade process.

Keywords: Mannich reaction; alkaloids; catalysis; total synthesis; vincadifformine.