Applications of ENDOR spectroscopy to radicals of low symmetry: Radical anions of 2-phenylcycl[3.2.2]azines☆

Abstract The radical anions of 2-phenylcycl[3.2.2]azine and 6-methyl-2-phenyl-5-azacycl-[3.2.2]azine were prepared by reaction with Na and with Li. Proton hyperfine couplings have been determined using electron-nuclear double resonance (ENDOR) spectroscopy. Assignments of couplings have been made by a combination of four methods: radio frequency coherence effects, calculations of relative ENDOR intensities, computer simulation of the ESR spectra, and MO calculations of π-spin distribution. Successful use of the two first methods has experimentally corroborated the theory of ENDOR line-shapes in the presence of both saturating and non-saturating nuclear radio frequency fields.