Electron spin resonance, ENDOR and TRIPLE resonance of some 9,10-anthraquinone and 9,10-anthraquinol radicals in solution

Abstract

E.s.r., ENDOR and TRIPLE resonance spectra have been recorded for 2-methylanthraquinone, anthraquinone-2-sulphonate and anthraquinone-2,6-disulphonate radical anions, and in a strongly acidic medium for 2-methylanthraquinol, anthraquinol-2-sulphonate and anthraquinol-2,6-disulphonate radical cations.

The hyperfine coupling constants (h.f.s.) and g factors are given. The ENDOR spectra show there to be more h.f.s. than were detected earlier by e.s.r. spectroscopy. The spectra of the di-deutero radicals of the anthraquinols and the assignment of h.f.s. are discussed.