Electric-field effects in nuclear magnetic resonance spectroscopy. Part IV. Substituted β-diketone complexes

Abstract

The effect of substituents in the chelate ring of several acetylacetonato-complexes is investigated by a study of the ¹H and ¹³C chemical shifts and the ¹³C–¹H spin–spin coupling constants of the methyl and methine groups. The polar complexes show different changes from the nonpolar complexes, which is qualitatively explained in terms of electric field effects as modified by polarisation of the substituent.