Spectroscopic studies. Part III. Proton magnetic resonance spectra and solvent shifts of some αβ-unsaturated ketones

Abstract

The ¹H n.m.r. spectra of several αβ-unsaturated ketones of fixed and labile conformations have been determined in benzene and carbon tetrachloride solutions and their solvent shifts recorded. Although the solvent shift data are consistent with the known conformations of these ketones, only an approximate relationship between solvent shift and degree of coplanarity could be found.

The approximate conformation of αβ-unsaturated ketones may also be determined using solvent shift data in solvents other than aromatic complexing solvents.