13 C CP MAS NMR, FTIR, X-ray diffraction and PM3 studies of some N -(ω-carboxyalkyl)morpholine hydrohalides
作者:Z. Dega-Szafran、I. Gąszczyk、D. Maciejewska、M. Szafran、E. Tykarska、I. Wawer
DOI:10.1016/s0022-2860(00)00754-7
日期:2001.1
centrosymmetric dimer, connected by two N + –H⋯Cl − (3.095(1) A) and two O–H⋯Cl − (3.003(1) A) hydrogen bonds. 13 C CP MAS NMR spectra, contrary to the solution, showed non-equivalence of the ring carbon atoms. The PM3 calculations predict a molecular dimer without proton transfer for an HCl complex, while for an HBr complex an ion pairs with proton transfer, and reproduces correctly the conformation of both
摘要 N -(ω-羧基烷基)吗啉盐酸盐, OC 4 H 8 N(CH 2 ) n COOH·HCl, n = 1–5, 被 13 C 交叉极化 (CP) 魔角旋转 (MAS) NMR 分析, FTIR 和 PM3 计算。N-(3-羧丙基)吗啉盐酸盐(n = 3)的结构已通过X射线衍射法在100 K下解析并精制至R = 0.031。晶体为单斜晶系,空间群 P 2 1 / c , a =14.307(3), b =9.879(2), c=7.166(1) A , β =93.20(3)°, V=1011.3(3) A 3,Z=4。在该化合物中,氮原子被质子化,两个分子形成中心对称二聚体,由两个 N + –H⋯Cl − (3.095(1) A) 和两个 O–H⋯Cl − (3.003(1) A) 氢键连接. 与溶液相反,13 C CP MAS NMR 谱显示环碳原子不等价。PM3 计算预测 HCl