Efficient Synthesis of Salts of the Tetrakis(perfluoroorgano)borate Anion, [B(CFCF2)4]-

The synthesis and the NMR spectra of the tetrakis(trifluorovinyl)borate salts M[B(CFCF2)4] (M = Li, K, Cs, [NR1R23]) as well as the X-ray crystal structure of the tetramethylammonium salt are reported. These salts were prepared by the reaction of boron trichloride with bis(trifluorovinyl)di-n-butyltin in the presence of tri- and tetraalkylammonium or alkali-metal chlorides in dichloromethane.