Tetrazole-Substituted Five, Six, and Seven-Membered Cyclic Amines Bearing Perfluoroalkyl Groups - Efficient Synthesis by Azido-Ugi Reaction

The application of perfluoroalkylated cyclic imines in azido-Ugi reactions was studied. It was shown that the reaction allows access to five-, six- and seven-membered perfluoroalkylated cyclic amines connected to a tetrazole ring. The scope and limitations of this approach are discussed. When benzyl isocyanide was used in the azido-Ugi reaction, it was shown that the tetrazole products could easily be debenzylated by catalytic hydrogenation to form 1H-tetrazoles in excellent yields.