Calculation of17O-NMR Chemical Shifts of Carbonyl Groups in Substituted Benzoyl Halides

Based on chemical shift measurements inN-phenylacetamides,N-phenyl-benzamides,-Nphenyl-o-hydroxybenzamides and methyl-Nphenylcarbamates,an equa-tion:cδal=0δn+C×(Δo+Δm+Δp) for calculating carbonyl17O-NMR chemical shifts of substituted-Nphenylamides was formulated.Thirteen substituent parameters were ob-tained with least-square linear regression.Experimentally measured17O chemical shifts of 47 substituted-Nphenylamides were used as the test set to examine the accuracy of the calculated results.The confidence limit was found to be 99.5% and the calculating errors for above 95% compounds were less than 3.0(relative errors 0.3%).