Unstable intermediates. Part XXXIX. The structure of iminoxy-radicals deduced from their electron spin resonance spectra in rigid media

Abstract

The electron spin resonance spectra of rigid solutions of chemically prepared iminoxy-radicals have been measured and analysed. They were generally identical with the spectra obtained from the corresponding γ-irradiated oximes. The spin-density distribution and the CNO bond angle calculated from the 14N hyperfine tensor are largely unaffected by the complexity of the iminoxy-radical.Deviations from this generalisation are discussed in terms of possible orientations of the iminoxy-group as also are anisotropic proton interactions detected for the radicals derived from anthraquinone monoxime and fluorenone oxime. The unique isotropic proton interaction exhibited by these latter radicals is positive.