The effect of solvents on the 13C NMR chemical shifts of the carbonyl carbon and the rotational barriers of N,N-dimethylbenzamide

The ¹³C solvent induced chemical shifts (SICS) of the carbonyl carbon and the thermodynamic barriers to rotation about the C? N bond of N,N-dimethylbenzamide are linearly related to the solvent parameter, E_T(30). A multi-parametric solvent parameter approach indicates that the SICS are influenced equally by polar effects and hydrogen-bond donor effects. Rotational barriers for N,N-dimethylbenzamide may, in principle, be determined by measurement of the ¹³C chemical shift of the carbonyl carbon in a particular solvent.