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The asymmetric unit of the title compound, 2C5H3ClO2S·C10H8N2, is comprised of a molecule of 3-chlorothiophene-2-carboxylic acid (3TPC) and half of a molecule of 4,4′-bipyridine (BPY). A distinctive O--H′N-based synthon is present. Cl′Cl and π-π stacking interactions further stabilize the crystal structure, forming a two-dimensional network parallel to the bc plane. [ABSTRACT FROM AUTHOR]

The asymmetric unit of the title co-crystal, C12H9N5O0.5C6H10O4, consists of one molecule of N6-benzoyladenine (BA) and one half-molecule of adipic acid (AA), the other half being generated by inversion symmetry. The dihedral angle between the adenine and phenyl ring planes is 26.71 (7)°. The N6-benzoyladenine molecule crystallizes in the N(7)--H tautomeric form with three non-pro tonated N atoms. This tautomeric form is stabilized by intramolecular N--H⋯O hydrogen bonding between the carbonyl (CO) group and the N(7)--H hydrogen atom on the Hoogsteen face of the purine ring, forming an S(7) ring motif. The two carboxyl groups of adipic acid interact with the Watson-Crick face of the BA molecules through O--H⋯N and N--H⋯O hydrogen bonds, generating an R2²(8) ring motif. The latter units are linked by N--H⋯N hydrogen bonds, forming layers parallel to (105. A weak C--H⋯O hydrogen bond is also present, linking adipic acid molecules in neighbouring layers, enclosing R²2(10) ring motifs and forming a three-dimensional structure. C=O⋯π and C--H⋯π interactions are also present in the structure. [ABSTRACT FROM AUTHOR]

Abstract: In the present study 1,2-bis(4-pyridyl)ethane (BPA) crystallizes with 2-chlorobenzoic acid (2CBA), 4-methylbenzoic acid (4MBA), phthalic acid (PA), succinic acid (SA) and adipic acid (AA) to yield co-crystals BPA.2CBA (1), BPA.4MBA (2), BPA.PA (3), BPA.SA (4) and BPA.AA (5) respectively. All the five co-crystals are constituted by the utilization of the (7) synthon, created by the combination of hard N-H⋯O and complementary soft C–H⋯O hydrogen bonds. 1 and 2 illustrate the formation of three component aggregate as in both cases BPA interacts with carboxylic acids to form supramolecular ladder-type assembies. Molecular recognition in co-crystals 3–5 results in the formation of extended infinite tapes and differ further as a consequence of the soft C–H⋯O bonds and stacking interactions. Structure 3 shows the formation of zig-zag tapes while 4 and 5 form linear infinite tapes. Structure 4 shows isostructural behaviour with an analogous structure previously reported (Bowes et al. (2003) ).The isostructurality is because of the structural resemblance between both the entities in the co-crystals – fumaric acid/succinic acid and 1,2-bis(4-pyridyl)ethane/1,2-bis(4-pyridyl)ethene. Compound 5 shows good degree of resemblance with another reported analogous structure-1,2-bis(4-pyridyl)ethene adipic acid. (Zhang et al. (2003) ). Structure 5 and the reported structure form similar supramolecular sheets through intertape interactions differing from each other only in the alignment of neighboring tapes. The linear tapes in both the cases are linked laterally through different C–H⋯O interactions and ventrally through different stacking interactions. This work illustrates the construction of different supramolecular architectures and the role of weak C–H⋯O hydrogen bonds and stacking interactions in the higher level of supramolecular organization. [Copyright &y& Elsevier]