节点文献

Na₄-CyDTA空间位阻的动态核磁共振研究

Dynamic NMR study on steric hindrance of Na₄-CyDTA

推荐 CAJ下载
PDF下载
不支持迅雷等下载工具，请取消加速工具后下载。

【Author】 LIU Guang-min1,LI Fei2,MAO You-gang2(1.College of Chemical Engineering,Harbin Engineering University,Harbin 150001,China;2.Institute of Theoretical Chemistry,Jilin University,Changchun 130023,China)

【机构】哈尔滨工程大学化工学院；吉林大学理论化学研究所；吉林大学理论化学研究所黑龙江哈尔滨150001；吉林长春130023；

【摘要】用动态核磁共振(DNMR)的方法研究了Na4CyDTA乙羧基质子1H NMR谱随温度的变化关系,结果表明,常温下由于乙羧基旋转受到空间阻碍导致其1H NMR谱分裂为1组AB谱,随温度升高,AB谱的化学位移差减小.通过拟和化学位移差与温度的关系,计算出了Na4CyDTA中阻碍乙羧基旋转的能垒为16.95 kJ/mol.更多还原

【Abstract】 The temperature dependence of 1H-NMR spectrum of acetate methylene protons in Na4-CyDTA was studied by dynamic nuclear magnetic resonance(DNMR).An AB pattern on the acetate proton resonance was observed,and the chemical shift difference of the acetate protons decreased with the increase of the temperature.The AB pattern of acetate protons was result from the steric hindrance.The energy of 16.95 kJ/mol for the rotation of C—N bond was obtained through the simulation of the relationship between chemical shift difference and temperature.更多还原