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.
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.
出处
《分子科学学报》
CAS
CSCD
2005年第5期1-4,共4页
Journal of Molecular Science
基金
国家自然科学基金资助项目(29734130)
关键词
空间位阻
旋转受阻几率
能垒
CyDTA
steric hindrance
probability of rotation hindrance
energy barrier
CyDTA
