metal-organic compounds
Open access
In the title polymeric compound, [Cu(C8H5O3)2(C4H4N2)(H2O)2]n, the CuII atom is located on a twofold rotation axis and has a slightly distorted octahedral coordination sphere. In the equatorial plane, it is coordinated by two carboxylate O atoms of two symmetry-related monodentate formylbenzoate anions and by two N atoms of the bridging pyrazine ligand, which is bisected by the twofold rotation axis. The axial positions are occupied by two O atoms of the coordinating water molecules. In the formylbenzoate anion, the carboxylate group is twisted away from the attached benzene ring by 6.2 (2)°, while the benzene and pyrazine rings are oriented at a dihedral angle of 68.91 (8)°. The pyrazine ligands bridge the CuII cations, forming polymeric chains running along the b-axis direction. Strong intramolecular O—HO hydrogen bonds link the water molecules to the carboxylate O atoms. In the crystal, O—HwaterOwater hydrogen bonds link adjacent chains into layers parallel to the bc plane. The layers are linked via C—HpyrazineOformyl hydrogen bonds, forming a three-dimensional network. There are also weak C—Hπ interactions present.
metal-organic compounds
Open access
The polymeric title compound, [Cd(C8H5O3)2(C4H4N2)(H2O)]n, contains two 4-formylbenzoate (FB) anions, one pyrazine molecule and one coordinating water molecule; the FB anions act as bidentate ligands. The O atom, the aldehyde H atom and the benzene ring of one of the FB anions are disordered over two positions. The O atoms were freely refined [refined occupancy ratio 0.79 (2):0.21 (2)], while the aldehyde H atoms and the benzene ring atoms were refined with fixed occupancy ratios of 0.8:0.2 and 0.5:0.5, respectively. In the ordered FB anion, the carboxylate group is twisted away from the attached benzene ring (A) by 22.7 (8)°. In the disordered FB anion, the corresponding angles are 15.6 (10) and 11.4 (11)° for rings B and B′, respectively. Benzene rings A and B are oriented at a dihedral angle of 24.2 (7), A and B′ at 43.0 (8)°. The pyrazine ring makes dihedral angles of 67.5 (4), 89.6 (7) and 86.2 (7)°, respectively, with benzene rings A, B and B′. The pyrazine ligands bridge the CdII cations, forming polymeric chains running along the b-axis direction. In the crystal, O—Hwater Ocarboxylate hydrogen bonds link adjacent chains into layers parallel to the bc plane. These layers are linked via C—Hpyrazine Oformyl hydrogen bonds, forming a three-dimensional network. π–π interactions [centroid–centroid distances = 3.870 (11)–3.951 (5) Å] further stabilize the crystal structure. There is also a weak C—Hπ interaction present.
metal-organic compounds
Open access
In the title polymeric compound, [Ni(C8H5O3)2(C4H4N2)(H2O)2]n, the NiII atom is located on a twofold rotation axis and has a slightly distorted octahedral coordination sphere. In the equatorial plane, it is coordinated by two carboxylate O atoms of two symmetry-related monodentate formylbenzoate anions and by two N atoms of the bridging pyrazine ligand, which is bisected by the twofold rotation axis. The axial positions are occupied by two O atoms of the coordinating water molecules. In the formylbenzoate anion, the carboxylate group is twisted away from the attached benzene ring by 7.0 (6)°, while the benzene and pyrazine rings are oriented at a dihedral angle of 66.2 (3)°. The pyrazine ligands bridge the NiII cations, forming polymeric chains running along the b-axis direction. Intramolecular O—HO hydrogen bonds link the water ligands to the carboxylate O atoms. In the crystal, water–water O—HO hydrogen bonds link adjacent chains into layers parallel to the bc plane. Pyrazine–formyl C—HO hydrogen bonds link the layers, forming a three-dimensional network. There are also weak C—Hπ interactions present. The title compound is isotypic with the copper(II) complex [Çelik et al. (2014a). Acta Cryst. E70, m4–m5].
organic compounds
Open access
In the title compound, C17H17NO2, the carbazole skeleton includes an ethoxycarbonyl group at the 3-position. The indole three-ring system is almost planar [maximum deviation = 0.065 (2) Å], and the ethyl ester group is inclined to its mean plane by 15.48 (2)°. In the crystal, there are π–π stacking interactions between parallel benzene rings and between parallel benzene and pyrrole rings of adjacent molecules [centroid–centroid distances = 3.9473 (8) and 3.7758 (8) Å, respectively]. Weak C—Hπ interactions are also present.
organic compounds
Open access
In the title compound, C15H15NO, the carbazole skeleton includes a methanol group at the 3-position. The indole ring system is almost planar [maximum deviation = 0.045 (2) Å]. In the crystal, O—HO hydrogen bonds link the molecules into zigzag chains along the b-axis direction. There are weak C—Hπ interactions within the chains and linking neighbouring chains forming sheets lying parallel to (001).