Base-Promoted Double-Bond-Migration/Hydrolysis/Isomerization of 4-Aryl-1,1,1-trifluorobut-2-en-2-yl Trifluoromethanesulfonates: A Metal-Free Approach to β-Trifluoromethyl Ketones

摘要

A method for the synthesis of β-trifluoromethyl ketones promoted by a base is described. In the presence of DBU, 1-aryl-4,4,4-trifluoromethylbutanones with various functional groups were obtained through the reaction of 4-aryl-1,1,1-trifluorobut-2-en-2-yl trifluoromethanesulfonates with water in moderate to excellent yields. The reaction underwent a double-bond-migration/hydrolysis/isomerization pathway, and 1-aryl-4,4,4-trifluorobut-2-en-1-ols were determined as the key intermediates. Both electron-withdrawing and electron-donating groups, such as fluoro, chloro, bromo, ester, cyano, trifluoromethyl, alkyl, and alkoxy, were tolerated well in this reaction.