[3872-23-9] · CCuF3S · Trifluoromethylthiocopper(I) · (MW 164.63)
(source of nucleophilic CF3S for preparation of aryl and vinyl sulfides)
Physical Data: mp 113-115 °C (1:1 DMF adduct).
Solubility: sol ether.
Form Supplied in: copper-colored solid; commercially available.
Preparative Methods: can be prepared by two different procedures (eq 1). Heating of finely divided Copper powder with bis(trifluoromethylthio)mercury neat at 80-100 °C until the appearance of an orange color persists, and then heating for 30 min at 150 °C, gives the desired product upon cooling, ether extraction, and evaporation.1,2 Stirring of copper powder and bis(trifluoromethyl) disulfide in DMF for 1 h gives trifluoromethylthiocopper as its 1:1 DMF adduct.3,4 Additionally, this reagent has been prepared by metal exchange of trifluoromethylthiosilver with Copper(I) Bromide.5
Handling, Storage, and Precautions: stable for several months when stored over phosphorus pentoxide at ambient temperature. Use in a fume hood.
Trifluoromethylthiocopper has been employed in reactions with bromodibenzocycloheptenones to synthesize precursors to tricyclic antipsychotic agents (eq 2).6 Conveniently, the copper reagent is formed from its mercury salt and copper (see eq 1) in the presence of the aryl bromide, and then reacted in situ to give the aryl sulfide in high yield. These aryl sulfides have also been prepared by heating a diaryl disulfide with trifluoromethylthiocopper in acetonitrile (eq 3). 1,2-Dithioalkenes, made with trifluoromethylthiocopper, have served as precursors to 1,2-bis(trifluoromethylthio)alkynes. The alkynes are prepared in three steps from 1,2-dibromoethene in good yield (eq 4).7
William J. Hoekstra
The R. W. Johnson Pharmaceutical Research Institute, Spring House, PA, USA