The Reaction of Cyclic Carbinol Amides with Triflic Anhydride as a Method to Prepare α-Trifluoromethyl-Sulfonamido Furans

[reaction: see text] A novel synthesis of alpha-trifluoromethyl-sulfonamido furans via the reaction of cyclic carbinol amides with triflic anhydride has been developed. The reaction proceeds under very mild conditions with a wide set of representative lactams to provide the alpha-trifluoromethyl-sulfonamido-substituted furan in high yield. Rapid access to a 5-substituted indoline can be achieved by thermolysis of the N-but-3-enyl-substituted sulfonamido furan.