Proton–coupled¹³C nuclear magnetic resonance spectra involving¹³C–¹H spin–spin coupling to hydroxyl-protons, a complementary assignment aid

Abstract

Two-, three- and four-bond spin–spin coupling between 13C and hydrogen-bonded hydroxy-protons, identified by deuterium exchange, is shown to aid the assignment of 13C n.m.r. spectra in a series of 5-hydroxyflavones and flavonones.