The 4-chloro- [C14H11ClN2O2, (I)], 4-bromo- [C14H10BrN2O2, (II)] and 4-diethylamino- [C18H21N3O2, (III)] derivatives of benzylidene-4-hydroxybenzohydrazide, all crystallize in the same space group (P21/c), (I) and (II) also being isomorphous. In all three compounds, the conformation about the C=N bond isE. The molecules of (I) and (II) are relatively planar, with dihedral angles between the two benzene rings of 5.75 (12) and 9.81 (17)°, respectively. In (III), however, the same angle is 77.27 (9)°. In the crystal structures of (I) and (II), two-dimensional slab-like networks extending in theaandcdirections are formedviaN—H...O and O—H...O hydrogen bonds. The molecules stack head-to-tailviaπ–π interactions involving the aromatic rings [centroid–centroid distance = 3.7622 (14) Å in (I) and 3.8021 (19) Å in (II)]. In (III), undulating two-dimensional networks extending in thebandcdirections are formedviaN—H...O and O—H...O hydrogen bonds. The molecules stack head-to-headviaπ–π interactions involving inversion-related benzene rings [centroid–centroid distances = 3.6977 (12) and 3.8368 (11) Å].
苄叉-4-羟基苯甲酰肼的 4-氯-[C14H11ClN2O2,(I)]、4-溴-[C14H10BrN2O2,(II)]和 4-二乙氨基-[C18H21N3O2,(III)]衍生物都在同一空间群(P21/c)中结晶,(I)和(II)也是同构的。在这三种化合物中,关于 C=N 键的构象均为 E。(I) 和 (II) 的分子相对平面,两个苯环之间的二面角分别为 5.75 (12) 和 9.81 (17)°。而在(III)中,同一角度为 77.27 (9)°。在 (I) 和 (II) 的晶体结构中,通过 N-H...O 和 O-H...O 氢键形成了沿 a 和 c 方向延伸的二维板状网络。分子通过涉及芳香环的π-π 相互作用从头到尾堆积起来[(I) 中的中心-中心距离 = 3.7622 (14) Å,(II) 中的中心-中心距离 = 3.8021 (19) Å]。在 (III) 中,通过 N-H...O 和 O-H...O 氢键形成了沿带方向延伸的波状二维网络。分子头对头通过涉及反转相关苯环的π-π 相互作用堆叠[中心-中心距离 = 3.6977 (12) 和 3.8368 (11) Å]。