Solvent effects on 13C and 1H NMR shielding of cyclic ketones: An experimental and theoretical study

1H and 13C NMR chemical shifts of various cyclic ketones from four to seven-membered rings have been measured and compared with calculated data in 17 different solvents. The solvent effects on NMR spectra were simulated with the polarizable continuum model (PCM). Magnetic shielding tensors were performed using the DFT coupled gauge-included atomic orbital calculations. A multi-linear-regression analysis has been carried out using the Kamlet-Abboud-Taft (KAT) solvatochromic parameters in order to elucidate and quantify the solvent effects on the 1H and 13C chemical shifts of the select compounds. It has been found that there is a good correlation between the solvent induced chemical shifts of 13C and π∗ scale of solvent polarity. 1H chemical shifts are affected mainly by polarity-polarizability and basicity of the solvent. The agreement between the calculated and the experimental data is good in all instances.