metal-organic compounds
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The title compound, {[Zn2(CH3CO2)3(OH)(C6H7ClN2)]·C2H5OH}n, has alternating octahedrally and tetrahedrally coordinated Zn2+ ions. The octahedral coordination sphere is composed of one N atom of the monodentate diaminochlorobenzene ligand, three acetate O atoms and two bridging hydroxide ligands. The tetrahedral coordination sphere consists of three acetate O atoms and the hydroxide ligand. The zinc ions are bridged by acetate and hydroxide ligands. The result is a laddered-chain structure parallel to [100] with ethanol solvent molecules occupying the space between the chains. The diamine ligand chlorine substitutent is disordered over two equally populated positions as a result of a crystallographically imposed inversion center between adjacent ligands. The ethanol solvent molecule exhibits disorder with the two components having refined occupancies of 0.696 (11) and 0.304 (11). O—HO hydrogen bonds form between the hydroxide ligand and the ethanol solvent molecule. N—HO and N—HN hydrogen bonding between the uncoordinated amine group and the acetate ligands and the coordinated amine group are also observed.
organic compounds
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The title compound, C20H18N4, was obtained via the condensation of 4,5-dimethylbenzene-1,2-diamine with pyridine-2-carbaldehyde. The plane of the 2-(pyridin-2-yl) substitutent is canted by 2.75 (11)° from the plane of the benzimidazole system. The molecule exhibits an S(6) C—HN intramolecular hydrogen-bond motif. In the crystal, C—HN hydrogen bonds link pairs of molecules related by a crystallographic inversion center, forming R22(20) rings. Additional weak C—HN hydrogen bonds result in C(9) chains parallel to [001].
organic compounds
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4-Bromo-2-(5-bromothiophen-2-yl)-1-[(5-bromothiophen-2-yl)methyl]-5,6-dimethyl-1H-benzimidazole
The title compound, C18H13Br3N2S2, was obtained via the reaction of N-bromosuccinamide with 5,6-dimethyl-2-(thiophen-2-yl)-1-[(thiophen-2-yl)methyl]-1H-benzimidazole. The compound exhibits rotational disorder of the 5-bromothiophen-2-yl substituent with a refined major:minor occupancy ratio of 0.876 (7):0.124 (7). The 5-bromothiophen-2-yl mean plane is canted to the benzimidazole plane by 20.0 (4) and 21 (4)° in the major and minor components, respectively. In the crystal, weak C—HN interactions link the molecules into infinite C(7) chains along the 21 axes.
organic compounds
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The title molecule, C20H20N2S2, is T-shaped and consists of a nearly flat 5,6-dimethyl-2-(5-methylthiophen-2-yl)benzimidazole system approximately perpendicular to the 5-methylthiophen-2-ylmethyl substituent. The 5,6-dimethyl-2-(5-methylthiophen-2-yl)benzimidazole system is rotationally disordered about the two imidazole N atoms as approximated by a twofold rotation axis with a refined major/minor occupancy ratio of 0.884 (2):0.116 (2). The benzimidazole ring system is essentially planar, the largest deviations being 0.026 (2) and 0.044 (18) Å in the major and minor components, respectively. The interplanar angles between the benzimidazole unit and the 5-methylthiophen-2-yl substituent are 10.8 (3) and 8(3)° in the major and minor components, respectively, and the corresponding angles with the 5-methylthiophen-2-ylmethyl substituent are 88.12 (8) and 89.5 (4)°. In the crystal, molecules are oriented with their 2-(5-methylthiophen-2-yl)benzimidazole mean planes approximately parallel to (11-3 and appear to be held together by π–π [2-thiopheneimidazole centroid–centroid distance = 4.1383 (7) Å] and C—Hπ contacts. A weak C—HN hydrogen bond generates infinite chains parallel to [100].
research communications
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The structures of three lead(II) coordination polymers are reported. One exhibits a two-dimensional structure, whereas the other two are one-dimensional. All three exhibit bidentate bridging acetate and monodentate benzene-1,2-diamine ligands. The extended structures reveal extensive hydrogen-bonding networks involving the diamine and acetate ligands.