HOMOGENEOUS CATALYTIC FLUOROALKYLATION OF THIOPHENOLS, PHENOLS AND PYRROLE BY FREONS BrCF2CF2Br AND CF2ClCFCl2

he use of sulfur dioxide as an electron transfer mediator in the presence of nitrogen bases permits the rather selective fluoroalkylation of thiophenols, phenols, and pyrrole by Freons BrCF2CF2Br and CF2ClCFCl2 under mild conditions. In the case of thiophenols, the fluoroalkylation occurs to give polyfluoroalkyl aryl sulfides, while phenols and pyrrole are alkylated in the ring. Effects were found for the electronic structure of the substrates and basicity of the medium (pKa of the pyridines) on the oxidation–reduction properties of the reagents and the efficiency of the reactions studied.