A novel synthesis of α-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 α-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.
