Rotational isomerism in epifluorohydrin

Abstract

The complete analysis of the 1H and 19F n.m.r. spectra of epifluorohydrin in four different solvents is reported. The parameters obtained are used to predict the predominant rotational isomers of the molecule. The long-range coupling constants to fluorine are opposite in sign, in accordance with recent results, and the long-range proton–proton coupling constants are small or negligible. A large chemical shift difference between the protons of the CH2F group is explained on the grounds of the proposed rotational isomers, and the anisotropic effect of the epoxide ring.