Trifluoroacetic acid-promoted intramolecular hydroamination of unfunctionalized olefins bearing electron-rich amino groups

Trifluoroacetic acid was found to be effective in intramolecular hydroamination of unfunctionalized olefins bearing electron-rich amino groups, and the corresponding N-heterocycles were obtained in good isolated yields. The scope of the substrates was investigated, and a possible reaction mechanism was proposed. Substituents on CC double bonds and amino groups of the substrates showed drastic effects on the course of the reactions.