Carbonyl 17O-NMR Chemical Shifts of Substituted Benzamides
取代苯甲酰胺的羰基17O-NMR化学位移研究

This paper provides a equation, δcal(17O)=δ0n+C×Σ Δ, for calculating carbonyl 17O chemical shifts of substituted benzamides, substituted N-methyl benzamides and substituted N, N-dimethyl benzamides. Eleven substituent parameters were obtained by least square linear regression analysis. The equation is checked regressively by 33 carbonyl \{\}\+\{17\}O chemical shifts of these compounds, and the results show that the confidence limit is 99.5% and the calculating errors (Δδ) of more than 90% of the compounds are less than 1.0 (relative errors less than 0.1%).