高等学校化学学报

高等学校化学学报 ›› 1993, Vol. 14 ›› Issue (2): 257.

• 研究论文 • 上一篇    下一篇

2,3-二氰基-2,3-二(p-X苯基)丁二酸二乙酯的分子构型和取代基电子效应对13C NMR谱的影响

杨第伦, 齐陈泽, 吴靖嘉, 崔育新, 刘有成   

  1. 兰州大学化学系, 兰州 730000
  • 收稿日期:1992-06-05 修回日期:1992-07-14 出版日期:1993-02-24 发布日期:1993-02-24
  • 通讯作者: 杨第伦
  • 基金资助:

    国家自然科学基金

The Influence of Molecular Configuration and Substltuent Electron Effect on 13C NMR Spectra of Diethyl 2,3-Dicyano-2,3-di(p-X substituted phenyl)succinate

YANG Di-Lun, QI Chen-Ze, WU Jing-Jia, CUI Yu-Xin, LIU You-Cheng   

  1. Department of Chemistry, Lanzhou University, Lanzhou, 730000
  • Received:1992-06-05 Revised:1992-07-14 Online:1993-02-24 Published:1993-02-24

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摘要： 测定了meso-和dl-2,3-二氰基-2,3-二(p-X苯基)丁二酸二乙酯(X=OCH3,CH3,H,Cl,NO2)的13CNMR谱。结果表明,中心碳—碳键两端相连基团的各碳原子的化学位移值相同,与dl-异构体相比,所有相应meso-异构体的乙氧羰基13CNMR吸收峰均处于高场。苯环对位取代基的Hammett基团常数σ与氰基碳原子和乙氧羰基中的羰基碳及次甲基碳的化学位移间线性相关,而且meso-异构体比dl-异构体有更好的线性关系。

关键词: 2, 3-二氰基-2, 3-二(p-X苯基)丁二酸二乙酯, 13C NMR化学位移, Hammett基团常数

Abstract: Meso- and dl-diethyl 2, 3-dicyano-2, 3-di(p-Xsubstituted phenyl)succinates(X=OCH3, CH3, H, Cl, NO2) are studied by means of 13C NMRspectra, The results indicate that the chemical shifts of carbon atoms in the same group on both sides of central carbon-carbon bond are equivalent, and the chemical shifts of C7-C9 atoms in the dl-isomers are smaller than that in corresponding meso-isomers.The average difference Δδβ-menvare found to be 1.80±0.16 ppm for C7, 0.39±0.16 ppm for C8 and 0.23±0.16 ppm for C9 respectivly.The plots of chemical shifts of C6, C7 and C8 atoms versus Hammett constant σ of substituents on p-position of benzene ring are good in linear line.

Key words: Diethyl2, 3-dicyano-2, 3-di(p-X substituted phenyl)succinate, 13C NMR chemical shift, Hammett substitutent constant

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