3,5-二甲基金刚胺盐酸盐的NMR研究

摘要

NMR核磁共振谱显示3,5-二甲基金刚胺盐酸盐是一个刚性结构,但其分子结构包含2个非对映体的立体构型形式.我们通过利用DEPT,1H-1H COSY,HSQC和HMBC等技术所测得的二维谱图数据对NMR数据进行了完整的归属分析,其中13CNMR谱图显示在δ=29～54 ppm之间的十组峰表示所有碳的共振,而且由于不同的分子构象导致在13C NMR谱中有3个不同的季碳峰和1H NMR中的2个不同的甲基峰.由于H5的叔碳H原子与邻近CH2的平面二面夹角均约为600,致使耦合常数极其小,波谱仪难以分辨它们从而使1H NMR峰为单重峰.%1H and 13C NMR spectroscopy was used to study the structure and configuration of 3,5-dimethyladamantanamine hydrochloride salt.Complete NMR assignments were made using DEPT.1H-1H COSY,HSQC and HMBC techniques.The NMR data indicated that the compound has a rigid structure and is comprised of two diastereomeric forms.There are ten peaks in the 13C NMR spectrum of the compound within the region δc 29～54 ppm.Because the compound has two different molecular configurations,there exist three peaks of quaternary carbons in the 13C NMR spectrum and two peaks of methyl groups in the 1H NMR spectrum.The two plane angles between the tertiary proton H5 and three adiacent CH2 are near 60,resulting in very small coupling constants among these protons.Consequently,the resonance of these protons can not be resolved and presents as a singlet in the 1H spectrum.