链状脂肪醚的^(17)O-NMR化学位移研究

STUDY OF^(17)O-NMR CHEMICAL SHIFTS OF CHAINED ALIPHATIC ETHERS

按甲基醚、乙基醚、正丙基醚、异丙基醚和叔丁基醚等五大类 ,提出了计算链状脂肪醚1 7O NMR化学位移的公式 :δcal=δ0n+Δα +Δβ +Δγ ,并通过线性回归法结合最小二乘法得到 2 9种取代基的参数 ,计算结果用以上五大类 1 4 7种化合物的 1 4 7个1 7O NMR化学位移数据为样本点作回归检验 ,置信度为 99.5 % ,计算误差Δδ小于 5 .0 (相对误差小于 0 .5 % )的1 7O NMR化学位移计算值约占 90 % .

Based on the results from five compounds: methylether, ethylether, n-propylether, i-propylether and t-butylether, an empirical equation: \$δ{cal\}=δ\-0+Δα+Δβ+Δγ\$ (Eq. \) was derived for calculating the \{\}\{17\}O-NMR chemical shifts of chained aliphatic ethers. Parameters were obtained for 29 substituents using linear regression in combination with least square analysis. The validity of Eq. \ was checked regressively by 147 \{\}\{17\}O-NMR chemical shifts of 147 chained aliphatic ethers. The confidence limit was 99.5 % and the calculating errors of about 90 % compounds were less than 5 ppm (relative errors 0.5 %).