ИСТИНА

The establishment of correlations between the molecular structure of organic compounds, the nature of intermolecular interactions, the supramolecular structures in crystals, and the properties of materials expands opportunities for the directed design of new compounds with desired physicochemical properties. Recently we established the empirical correlations between the supramolecular structure and its orientation in the crystals of terminal ethers of glycerol and benzodiazepines derivatives which suggest that 1D and 2D- supramolecular structures preferebly oriented along the shortest parameters of the unit cell. In this work we attempted to expand this approach to the supramolecular structure analysis of heterocyclic compounds of another type. The results of X-ray analysis of a series of synthesized N-(pyrrol-3yl)benzimidazolone derivatives containing additional aromatic fragments and several proton-donor and proton-acceptor groups are presented. According to the X-ray analysis the main molecule skeleton is not subject to changes in the crystals. It was showed that the differences in the geometry of the molecules of the studied compounds are associated only with different relative position of pyrrole substitutent and benzimidazolone system. Despite the several proton-donor and proton-acceptor centers, the realization of the same types of primary supramolecular structures could be pointed out in the crystals. For this series of compounds realis two types of centrosymmetric dimers. The first type H-dimer with participation the hydrogen atom of pyrrole cycle is observed for compounds 1–4. The second type dimer with participation in H-bonding the hydrogen atom of benzimidazolone system is observed for compound 2, 5. It should be noted that crystallization with the solvent molecule (in the case of compound 2, acetic acid in the ratio 1:1) does not prevent the formation of such dimers in crystal. Analysis of the supramolecular structure within the framework of the proposed approach shows that the realization of classical hydrogen bonds in the crystals of majority studied compounds leads to the binding of primary H-synthons into supramolecular structures, the orientation of which obeys this empirical rule. But, the dimensionality of supramolecular structures formed by the classical hydrogen bonds N–H...O depends on the number of independent molecules (Z') in the unit cell. In the case of crystallization with two independent molecules (Z'= 2) the supramolecular structure is represented by infinite layers. During reduction of the number of independent molecules to Z'= 1 the basic supramolecular structure is a stack of H-bonded molecules, but oriented along the lowest parameter of the unit cell. The conditions of realization of empirical correlation in the crystals of investigated benzimidazoles are explained basing on the calculation of the energy of various types of interactions.