Phenyldifluorosulfur(IV)yl salt, C6H5SF2+BF4−

The salt C6H5SF2+BF4− has been synthesized by the reaction of C6H5SF3 and BF3 in the aHF solution. C6H5SF2+BF4− is a colorless crystalline solid which attacks glass and is extremely moisture sensitive. In aHF it reacts with KF to give the starting material C6H5SF3 and KBF4. Vibrational spectra are characteristic of monosubstituted benzenes and BF4− ion, supporting the ionic formulation. Chemical analyses and mass spectrum give additional support for the proposed structure.