Me3SiCF3/AgF/Cu-A new reagents combination for selective trifluoromethylation of various organic halides by trifluoromethylcopper, CuCF3

An alternative copper halide-free route to obtain highly reactive trifluoromethylcopper species has been developed via the reaction of silver fluoride and trimethyl(trifluoromethyl)silane followed by a redox transmetallation with elemental copper. The composition of the reactive intermediate was investigated by means of UV/Vis/NIR, ESR, F-19 NMR spectroscopy and ESI mass spectrometry. Trifluoromethylcopper prepared by the oxidative transmetallation route exhibits excellent reactivity and selectivity in substitutions of iodine or bromine bond to aromatic or heterocyclic compounds for trifluoromethyl groups without any additional catalyst. (C) 2011 Elsevier B.V. All rights reserved.