An easy three step synthesis of perfluoroalkylated amphetamines

A general synthesis of perfluoroalkylated amphetamines is presented. Initially, 1-aryl-1-iodo-2-(perfluoroalkyl)ethylenes are prepared by radical addition of perfluoroalkyl iodides to arylacetylenes. Key step of the reaction sequence is the following dehydroiodination in the presence of n-BuLi to give 1-perfluoroalkyl-2-arylacetylenes in situ, which are reacted with secondary amines to produce perfluoroalkylated enamines in a new one pot procedure. Final hydrogenation yields the desired products in good yields. By using N,N-dibenzylamine or N-benzylamines the corresponding primary and secondary perfluoroalkylated amines are easily available.