Convenient synthesis of fluorinated alkanes and cycloalkanes by hydrogenation of perfluoroalkylalkenes under ultrasound irradiation

Synthesis of several 1,4-disubstituted cyclohexanes, by hydrogenation of sterically hindered and electron poor perfluoroalkyl alkenes, was performed, at room temperature under hydrogen at atmospheric pressure. Hydrogenation was difficult to achieve without ultrasound whatever catalyst and pressure (from 1 to 120 bar) used. Coupling of ultrasonic irradiation with metallic catalysis dramatically increased the efficiency of hydrogenation of perfluoroalkyl alkenes.