Bromination-Dehydrobromination/Debromination of N-Methyl-N-(2-phenylethenyl)trifluoromethanesulfonamide

摘要

We have recently synthesized the first N-alkenyl-substituted trifluoromethanesulfonamide, N-methyl-N-[(E)-2-phenylethenyl]trifluoromethanesulfonamide (I) [1]. With a view to obtain new trifluoromethanesulfonamide derivatives, we tried to synthesize adducts of I with various nucleophiles. However, compound I failed to react with methanol, ethanol, or diethylamine even on prolonged heating under reflux, but it readily took up bromine molecule in dioxane, and the resulting dibromo derivative readily underwent dehydrobromi-nation by the action of alcoholic alkali (Scheme 1).