Carbon‐13 and nitrogen‐15 NMR spectra of some methanesulphonanilides

The ¹³C and ¹⁵N NMR spectra of some ortho‐, meta‐ and para‐substituted methanesulphonanilides were recorded. Correlations of the ¹³C chemical shifts with the appropriate substituent chemical shifts (SCS) for monosubstituted benzenes were excellent and showed enhancement of the substituent effects at C‐1 (para to the substituent). The C‐1 chemical shifts were also examined by means of the dual substituent parameter (DSP) and DSP‐nonlinear resonance equations. The results indicate that the —NHSO₂ Me moiety is a weak electron donor. The ¹⁵N chemical shifts of the para‐substituted compounds were analysed by means of DSP equations and the results compared with those of related compounds. Ortho‐substituted compounds indicate the high sensitivity of ¹⁵N chemical shifts towards steric compression. T₁ and nuclear Overhauser enhancement data for the protonated carbons of methyl‐substituted compounds are given.