The radical-anions of various alkyl-iodides

Exposure of a range of alkyl and substituted alkyl iodides in methanol glasses at 77 K to ionizing radiation gave EPR spectra assigned to the alkyl radicals. Irradiation of the pure compounds gave central features assigned to the alkyl radical-iodide ion adducts, together with outer features assigned to the primary sigma*-radicals, R radical anion I.-. These novel results are discussed in terms of the role of the media in governing the species formed. In the case of the I-CH2CO2- and I-CH,OH derivates, species with very large hyperfine coupling to I-127 nuclei are thought to be the ax-radicals I-CH2CO2-I- and I-CH2O-I-, similar to the I-OMe- radicals previously studied.