Six hydrogen-bonded supramolecular frameworks assembled from organic acids and p-dimethylaminobenzaldehyde

Cocrystallization of the commonly available organic compound, p-dimethylaminobenzaldehyde, with a series of organic acids gave a total of six molecular adducts with the compositions: p-dimethylaminobenzaldehyde : (3,5-dinitrosalicylic acid) [(L)center dot(Hdsa), Hdsa = 3,5-dinitrosalicylic acid] (1), p-dimethylaminobenzaldehyde : (3-nitrophthalic acid) [(L)center dot(3-H(2)npa), 3-H(2)npa = 3-nitrophthalic acid] (2), p-dimethylaminobenzaldehyde : (4-nitrophthalic acid) [(L)center dot(4-H(2)npa), 4-H(2)npa = 4-nitrophthalic acid] (3), p-dimethylaminobenzaldehyde : (1,5-naphthalenedisulfonic acid) : (NH3)(2) [NH4 center dot(HL)center dot(nds(2-))center dot NH3, nds(-) = 1,5-naphthalenedisulfonate] (4), p-dimethylaminobenzaldehyde : (oxalic acid)(0.5) [(L)center dot(H(2)oa)(0.5), H(2)oa = oxalic acid] (5), and p-dimethylaminobenzaldehyde : (fumaric acid)(0.5) [(L)center dot(H(2)fum)(0.5), H(2)fum = fumaric acid] (6). The six molecular adducts have been characterized by X-ray diffraction technique, IR, and elemental analysis, and the melting points of all adducts were also reported. And their structural and supramolecular aspects are fully analyzed. Of the six adducts, only 4 is an organic salt and the other five are cocrystals. The crystal packing is interpreted in terms of the strong classical hydrogen bonds as well as other weak non-classical hydrogen bonds. The different families of non-covalent bonds contribute to the stabilization and expansion of the total high-dimensional (2D-3D) frameworks. (C) 2015 Elsevier B.V. All rights reserved.