Visible light enabled.- trifluoromethylation of Baylis- Hillman acetates: stereoselective synthesis of trisubstituted alkenes

A distinct visible light induced -trifluoromethylation of Baylis-Hillman acetates has been accomplished using eosin Y as a photoredox catalyst and bench stable Langlois' reagent (CF3SO2Na) as a CF3 source under metal-free conditions at room temperature to afford various trisubstituted alkenes. The product stereochemistry is predominantly trans (E), and involves trifluoromethylation followed by de-acetoxylation.