几种基于氨基酸甲酯的双对苯二甲酰胺,包括甘氨酸(1),β-丙氨酸(2),γ-氨基丁酸(3)和ε-氨基己酸(4),X (CH 2)n HNOC C 6 H 已合成4 CONH (CH 2)n X(X CO 2 CH 3, n = 1、2、3和5),并通过单晶X射线衍射和光谱法进行了表征:FT-IR,偏振FT- IR,拉曼,11 H NMR和13 C NMR。四个结构是通过酰胺官能团之间的经典N H = O氢键组装而成的,这些官能团将分子连接成与短轴平行的链。对纯净和氘代化合物的极化IR光谱进行的分析表明,弱的链间(“贯穿空间”)激子耦合涉及属于两个不同相邻链的两个紧密间隔的氢键。激子偶合强度随对苯二甲酸酰胺系统中亚甲基的添加而降低。对苯二甲酰胺的同位素效应表明,质子和氘核在晶格中的分布取决于涉及氢键的激子偶联的强度。
Molecules of the title compound, dimethyl N,N'-(1,4-benzenedicarboxamido)diacetate, C14H16N2O6, lie on inversion centres and are hydrogen bonded along a single direction that runs parallel to the crystallographic b axis. Glycine residues adopt a conformation which deviates slightly from that characteristic of the polyglycine II structure. An angle close to 27 degrees is found between the planar amide groups and the plane of the aromatic ring.