Generation and Characterization of the Tris(pentafluorophenyl)borane Radical Anion

Abstract

The anion derived from B(C6F5)3 has been detected by EPR, and the boron and fluorine hyperfine splitting constants have been determined. Treatment of B(C6F5)3 with the reductant Cp*2Co in THF at −50 °C rapidly results in a dark blue (λmax = 603 nm) paramagnetic solution containing the anion radical. The half-life for disappearance of λmax, about 10 min at room temperature, is consistent with that of the EPR signal.