Heterocyclic free radicals. Part V. An electron spin resonance investigation of the cation-radicals of 10-phenylphenoxazine and 10-phenylphenothiazine

Abstract

Isotropic e.s.r. spectra of the stable cation-radicals of 10-phenylphenoxazine and 10-phenylphenothiazine are described; hyperfine splittings are assigned on the basis of MO calculations and experiments on selectively deuteriated derivatives. For both radicals, good agreement is obtained between calculated and experimental splittings when it is assumed that the plane of the phenyl ring in the 10-position is twisted ca. 70° from the plane of the remainder of the radical.