高等学校化学学报

高等学校化学学报 ›› 1991, Vol. 12 ›› Issue (12): 1627.

• 研究论文 • 上一篇    下一篇

meso和dl 2,3-二氰基-2,3-二(p-取代苯基)丁二酸二乙酯的1H NMR研究

杨第伦, 齐陈泽, 崔育新, 党海山, 刘有成   

  1. 兰州大学化学系, 兰州, 730000
  • 收稿日期:1990-09-04 出版日期:1991-12-24 发布日期:1991-12-24
  • 通讯作者: 杨第伦
  • 基金资助:

    国家自然科学基金

Studies on the 1H NMR Spectra of meso and dl diethyl 2,3-dicyano-2,3-bis(p-substituted phenyl)succinates

Yang Di-lun, Qi Chen-ze, Cui Yu-xin, Dang Hai-shan, Liu You-cheng   

  1. Department of Chemistry, Lanzhou University, Lanzhou, 730000
  • Received:1990-09-04 Online:1991-12-24 Published:1991-12-24

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摘要： 测定了meso和dl2,3-二氰基-2,3-二(p-X苯基)丁二酸二乙酯(X=OCH3,CH3,H,Cl,NO2)的1HNMR谱及X为CH3相应二乙酯的1HNoesy谱。在meso和dl异构体中,苯环m-1H的化学位移与p-X的Hammett基团常数σ呈线性关系,c1H的化学位移仅受分子构型的影响,;△δdl-meso为负值,乙氧基中CH2和CH3的质子化学位移也只受分子构型的影响,△δdl-meso均为正值。

关键词: 1H NMR谱, 化学位移, 分子构型, 2, 3-二氰基-2, 3-二(p-取代苯基)丁二酸二乙酯

Abstract: The 1H NMR spectra of mesa and dl diethyl 2,3-dicyano-2,3-di(p-Xphenyl)succi-nates(X=OCH3, CH3, H, Cl, NO2) and 1H Noesy spectra of meso and dl isomers of the diethyl ester with X=CH3were determined by using Bruker Am 400 MHz superconducting NMR spectrometry. The corresponding proton of the substituent groups attached to the two central carbon atoms in the molecules are chemical shift equivalence. The average difference between o -1Habsorptions of phenyl in the dl-isomers and that in meso-isomers was found to be △δdl-meso= -120. 1 ± 6.1 Hz. All of the meso-isomers, then, have, methylene (ABX3system) and methyl in the ethoxy at upfield positions, and all of the dl-isorners have that at downfield positions, △δdl-meso= 53. 3 ± 5. 9 Hz and △δdl-meso= 53. 5 ± 5. 4 Hz for Aand Bprotons in the methyienes, and △δdl-meso=39. 3+3. 5 Hz for protons in the methyls. △δdl-meso is the mark of influence of molecular configuration on the chemical shift.

Key words: 1H NMR spectra. Chemical shift, Molecular configuration, Diethyl 2,3-dicyano-2,3-bis(p-substituted phenyDsuccinates

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