Electron spin resonance study of some radical anion intermediates from xanthen and related compounds

When xanthen, thioxanthen, and anthrone were reduced electrolytically in dimethylformamide the radical anions of the corresponding ketones were found to be formed. When anthrone was reduced with lithium and sodium metals under vacuum in tetrahydrofuran, an e.s.r. spectrum was obtained consistent with the formation of a mixture of the radical anions of anthrone and anthranol. This spectrum decayed and could not be regenerated, but further reactions were found to occur giving two further spectra, one of which was found to be due to the anthracene radical anion.