Electron spin resonance studies. Part XVIII. Reactions of some aldehydes and ketones, the corresponding oximes, and some nitroalkane anions with the titanium(III)–hydroxylamine system

Abstract

When solutions of titanium(III) chloride, hydroxylamine, and one of a number of aldehydes or ketones are mixed, shortly before passage of the combined solution through the cavity of an e.s.r. spectrometer, the spectrum of a radical of the type R¹R²C(OH)–NH–O· is observed; evidently the adduct R¹R²C(OH)–NHOH, which mediates in oxime formation, is both formed and oxidised exceptionally rapidly. These radicals are also formed by addition of the hydroxyl radical to oximes, at both pH 1 and 9, and analogous radicals are formed by the addition of the amino-radical to oximes. Both ·OH and ·NH₂ also add readily to the anions derived from some nitroalkanes. The hyperfine splitting constants of the radicals which have been examined are discussed.