The assignment of the 1H and the 13C NMR chemical shifts of N‐phenyl‐2,4‐dimethylbuta‐1,3‐diene‐1,4‐sultam

Abstract

AbstractThe assignment of the signals in the 13C and 1H NMR spectra of N‐phenyl‐2,4‐dimethylbuta‐1,3‐diene‐1,4‐sultam is difficult for the signal pairs C‐2 and C‐4, C‐1 and C‐3, (C‐1)H, (C‐2)CH3 and (C‐4)CH3. The 13C NMR spectrum recorded under gated decoupling conditions provide long‐range couplings which make possible an unambiguous assignment of the 13C NMR signal pairs. Application of the 1H CW off‐resonance decoupling technique in recording the 13C NMR spectra enables the assignment information from the 13C NMR spectrum to be transferred to the 1H NMR spectrum.