Organocatalytic enantioselective nucleophilic vinylic substitution by alpha-substituted-alpha-cyanoacetates under phase-transfer conditions.
The organocatalytic enantioselective formation of vinyl-substituted all-carbon quaternary stereocenters via nucleophilic vinylic substitution by alpha-substituted-alpha-cyanoacetates is presented. The reaction proceeds well for different alpha-substituted-alpha-cyanoacetates and beta-chloroalkenones using a dimeric cinchona alkaloid phase-transfer catalyst giving the products in good yield and with enantioselectivities up to 98% ee.
Bell
Mark
M
Danish National Research Foundation: Center for Catalysis, Department of Chemistry, Aarhus University, DK-8000 Aarhus C, Denmark.
Poulsen
Thomas B
TB
Jørgensen
Karl Anker
KA