Gowda B Thimme, Tokarčík Miroslav, Shakuntala K, Kožíšek Jozef, Fuess Hartmut
Acta Crystallogr Sect E Struct Rep Online. 2010 Jun 5;66(Pt 7):o1554. doi: 10.1107/S160053681002012X.
In the title compound, C(11)H(11)NO(3), the conformation of the N-H bond is anti to the C=O bond in the amide segment, while it is syn to the ortho-methyl group in the phenyl ring. In the maleamic acid unit, the amide C=O bond is anti to the adjacent C-H bond, while the carboxyl C=O bond is syn to the adjacent C-H bond. The C=O and O-H bonds of the acid group are in the relatively rare anti position to each other. This is an obvious consequence of the intra-molecular O-H⋯O hydrogen bond donated to the amide carbonyl group. The ortho-substituted phenyl ring makes a dihedral angle of 12.7 (1)° with the mean plane of the maleamic acid unit. In the crystal structure, inter-molecular N-H⋯O hydrogen bonds link the mol-ecules into zigzag chains parallel to [001]. These chains are further linked into sheet by weak π-π inter-actions [centroid-centroid distance = 3.425 (2) Å].
在标题化合物C₁₁H₁₁NO₃中，N - H键的构象在酰胺片段中与C = O键呈反式，而在苯环中与邻位甲基呈顺式。在马来酰胺酸单元中，酰胺C = O键与相邻的C - H键呈反式，而羧基C = O键与相邻的C - H键呈顺式。酸基团的C = O键和O - H键处于相对少见的反式位置。这是分子内O - H⋯O氢键供体作用于酰胺羰基的明显结果。邻位取代的苯环与马来酰胺酸单元的平均平面形成12.7 (1)°的二面角。在晶体结构中，分子间N - H⋯O氢键将分子连接成平行于[001]的锯齿链。这些链通过弱π - π相互作用[质心 - 质心距离 = 3.425 (2) Å]进一步连接成层。
