物理化学学报 >> 1988, Vol. 4 >> Issue (03): 244-249.doi: 10.3866/PKU.WHXB19880305

研究论文 上一篇    下一篇

苯并氮杂冠醚化合物在氘代氯仿中的溶剂效应的动态1H NMR研究

曾竟成; 沈联芳; 鲁天保; 吴成泰   

  1. 中国科学院武汉物理所波谱与原子分子物理开放研究实验室; 武汉大学化学系
  • 收稿日期:1986-09-15 修回日期:1987-03-30 发布日期:1988-06-15
  • 通讯作者: 曾竟成

DYNAMIC 1H NMR STUDIES OF SOLVENT EFFECT FOR BENZO-AZACROWN-ETHERS IN CDCl3 SOLUTIONS

Zeng Jingcheng*; Shen Lianfang;
Lu Tianbao; Wu Chengtai   

  1. Laboratory of Magnetic Resonance and Atomic and Molecular Physics; Wuhan Institute of Physics; Academia Sinica
    Chemistry Department; Wuhan University
  • Received:1986-09-15 Revised:1987-03-30 Published:1988-06-15
  • Contact: Zeng Jingcheng

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摘要： 本文讨论了样品浓度对苯并氮杂冠醚化合物-氘代氯仿溶液~1H NMR镨及~1H纵向弛豫时间的影响(稀释位移效应)。在实验基础上提出了苯并氮杂冠醚化合物在氯仿中的叔胺-叔铵盐交换作用机制。以此馐土讼∈臀灰菩в? 并得到巳止诿鸦衔锎邮灏返绞屣а蔚姆从ζ胶獬Ｊ齂_2和交换速率常数k, 另外, 本文还讨论了冠醚环中氮原子上取代基对稀释位移效应的影响,

Abstract: The influences (Dilution Shift Effect) of sample concentration on ~1H NMR spectra and spin-lattice relaxation times in benzo-azacrown-ether (CE) -CDCl_3 solutions were discussed in this paper. It was considered that the formation of hydrogen bond complex between CE and CDCl_3 is not the major cause leading to Dilution Shift Effect. Based on experiments, a reaction mechanism for CE in CDCl_3-“tertiary amine-tertiary amino salt exchange” was proposed, which has successfully explained the Dilution Shift Effect. The equilibrium constants K_2[(2.2±0.4)×10~(-2) mol L~(-1), (1.9±0.4)×10~(-2) mol L~(-1) and (1.3±0.4)×10~(-2) mol L~(-1) respectively] and exchange rate constants k[4500±1000 s~(-1), 15000±3000 s~(-1) and 6000±1500 s~(-1) respectively] for this mechanism of “tertiary amine-tertiary amino salt exchange” of I, II and III (see experimental section) were obtained through simulation of chemical shift and line shape of ~1H NMR spectra of CE in CDCl_3. Also, the effects of substitute groups of α—C to N on the Dilution Shift Effect were discussed.