Nuclear magnetic resonance coupling constants in p-benzoquinones

Abstract

By an analysis of the ¹³C satellite spectrum of p-benzoquinone, the following values for the coupling constants have been obtained: J_o= 10·7, J_m= 3·2, and J_p=–1·1 c./sec. The normal proton spectra of some substituted p-benzoquinones have also been analysed as an aid to the analysis of the p-benzoquinone spectrum. Theoretical coupling constants have been calculated using a MO theory, and the effect of the heteroatoms and of the geometry of the molecule on these values has been studied.