有机化学 ›› 2000, Vol. 20 ›› Issue (2): 237-242. 上一篇    下一篇

研究论文

基团共轭效应参数

聂长明;夏良树   

  1. 中南工学院化学工程系
  • 发布日期:2000-04-25

Conjugative effect parameters of groups

Nie Changming;Xia Liangshu   

  • Published:2000-04-25

以单取代苯为模型,假定间位代轭效应受阻,诱导效应在共轭体系中的传递因子为1/2,则基因的共轭效应参数:Rc=0.05(△δp-△δm)或Rc=0.05(δp-δm)△δp和△δm分别表示单取代苯对位和间位的^1^3CNMR化学位移相对于未取代母体增量,δp和δm分别为单取代苯对位和间位的^1^3CNMR化学位移。用上式计算了559个基团的共轭效应参数,其结果与文献报道值颇为一致,且呈明显的变化规律。

关键词: 基团, 共轭效应, 碳13核磁共振谱法, 化学位移, 苯P

Using monosubstituted benzene as a model and presuming: (1) the conjugative effect of meta - position is prohibited; (2) the transmit factor of induction effect in the conjugative system is 1/2, the experimental formula for the conjugative effect parameters can be expressed as follows: Where △δp and△δm refer to the deviations of ^1^3C NMR chemical shifts of para - and meta - positin of monosubstituted benzenes with respect to unsubstituted parent respectively. δp and δm refer to the ^1^3C NMR chemical shifts for para - position and metal - position respectively. Using the formula, conjugative effects parameters for 559 groups are calculated, and the results agree well with the observed values in the literature.

Key words: GROUP, CONJUGATIVE EFFECT, C13 NMR SPECTROMETRY, CHEMICAL SHIFT, BENZENE P

中图分类号: