ANION RADICALS OF SOME FLUOROBIPHENYLS

Potassium 4,4′-difluorobiphenylide, 4-fluorobiphenylide and potassium 3,3′-difluorobiphenylide are stable at -80° in the tetrahydrofuran. 4-Chlorobiphenyl, 4-bromobiphenyl and 4,4′-dibromobiphenyl apparently react with potassium at low temperatures to form radicals which decompose immediately by halide elimination. The ESR spectra of the 4,4′-difluorobiphenylide and 3,3′-difluorobiphenylide radicals and the polarographic behaviour, p-band positions, and results of LCAOMO calculations for the parent, neutral compounds are reported. © 1968.