Organocatalytic Enantioselective Nucleophilic Vinylic Substitution by α-Substituted-α-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.