The electron spin resonance spectra of semiquinones obtained from some heterocyclic quinones

Abstract

Radical anions of heterocyclic quinones and related compounds were generated in a static system in alkaline media. The unpaired electron distribution in several of the radicals could not be satisfactorily verified by simplified SCF calculations. It is shown that, using a smooth variation of splitting pattern with substitution in radicals related to phenoxyl, quite convincing assignments of the splitting patterns can be made based on comparison with related species.