Iminoxy free radicals derived from diethyl (1-hydroxyimino)phosphonates. An EPR study

Abstract

Iminoxy radicals containing the diethyl phosphonate group have been synthesized and characterized by means of EPR spectroscopy. Structures of the Z and E isomers have been established on the basis of hyperfine splitting due to ¹⁴N, ³¹P, and ¹H nuclei. The higher stability of the E isomer over the Z isomer has been established by analysis of anisotropic spectra. The source of a dependence of the ³¹P hyperfine constant on the solvent polarity is discussed.