Electron-Deficient Alkynes as Dipolarophile in Pd-Catalyzed Enantioselective (3 + 2) Cycloaddition Reaction with Vinyl Cyclopropanes

The activated alkynes have been used successfully for the first time as the dipolarophile in the palladium-catalyzed asymmetric (3 + 2) cycloaddition, affording highly functionalized cyclopentenes in good to high yields with high chemoselectivities and good to high enantioselectivities. The introduction of an additional carbonyl group at the α-position of the alkynyl esters is the key to activating the carbon-carbon triple bond. The reaction...