metal-organic compounds
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In the title compound, [Ni(C40H28N4S4)]·0.5C6H6, the NiII atom is in a square-planar geometry defined by four pyrrole N atoms. There is considerable buckling in the porphyrin ring with the dihedral angles between the N4 donor set and the pyrrole rings being in the range 16.24 (5)–22.47 (5)°. Each of the six-membered chelate rings is twisted about an Ni—N bond and the dihedral angles between diagonally opposite chelate rings are 21.36 (4) and 23.87 (4)°; each pair of rings is oriented in opposite directions. The methylthienyl rings are twisted out of the plane of the central N4 core with dihedral angles in the range 75.98 (2)–88.70 (5)°. All four methylthienyl groups are disordered over two sets of sites, as is commonly found with such groups, with occupancies of 0.553 (8):0.447 (8), 0.579 (7):0.421 (7), 0.796 (6):0.204 (6) and 0.956 (7):0.044 (7). The benzene solvent molecule was found to be present in half-occupancy.
organic compounds
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In the title compound, C11H9NO2Se, the pyridine and phenyl rings are almost perpendicular, with the dihedral angle between their mean planes being 79.16 (7)°. In the crystal, the molecules pack so as to form ruffled sheets in the (110) plane connected by weak C—HO interactions. In addition, there are weak π–π interactions between the mean planes of both the phenyl [centroid–centroid perpendicular distance of 3.591 (2) Å and slippage of 1.854 (2) Å] and pyridine rings [centroid–centroid perpendicular distance of 3.348 (2) Å and slippage of 1.854 (2) Å].
organic compounds
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The title compound, C22H30BrNO, is an alkoxyamine compound, an effective initiator in nitroxide-mediated free radical polymerization. It was prepared as a mixture of two diasteromers; the crystal for the X-ray analysis showed one of these as a pair of R,S and S,R enantiomers. The tert-butyl and isopropyl groups are in an almost anti conformation in the crystal [C—N—C—C torsion angle = −168.8 (1)°], and the methyl group of the ethoxy group is in an approximate anti relationship to the tert-butyl group. The dihedral angle between the phenyl and benzene rings is 33.12 (7)°. The Br atom is disordered over two positions, with occupancies of 0.9139 (16) and 0.0861 (16). In the crystal, weak C—HBr contacts link the molecules into chains along [-110].
organic compounds
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The title compound, C5H11NO2·H2O, is an isomer of the α-amino acid valine that crystallizes from water in its zwitterion form as a monohydrate. It is not one of the 20 proteinogenic amino acids that are used in living systems and differs from the natural amino acids in that it has no α-H atom. The compound exhibits hydrogen bonding between the water molecule and the carboxylate O atoms and an amine H atom. In addition, there are intermolecular hydrogen-bonding interactions between the carboxylate O atoms and amine H atoms. In the crystal, these extensive N—HO and O—HO hydrogen bonds lead to the formation of a three-dimensional network.
organic compounds
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The asymmetric unit of the title compound, C21H18ClFO3, contains two independent molecules. In one molecule (A), the 4-chlorophenyl, oxocyclohex-3-ene, carboxylate, and ethyl groups were refined as disordered over two sets of sites with a 0.684 (5):0.316 (5) ratio. The cyclohexene ring in the disordered molecule is in a slightly distorted envelope conformation for the major component (with the C atom bound to the carboxylate group being the flap atom) and in a screw-boat conformation for the minor component. In the ordered molecule (B), the cyclohexene ring is in a half-chair conformation. The dihedral angles between the mean planes of the fluoro- and chloro-substituted benzene rings are 89.9 (7) (only the major component is considered for A) and 76.4 (7)° (B). In the crystal, inversion dimers are observed along with weak C—HO hydrogen bonds, which form chains along [100].
organic compounds
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The title compound, C5H9NO4·H2O, is an isomer of the α-amino acid glutamic acid that crystallizes from water in its zwitterionic form as a monohydrate. It is not one of the 20 proteinogenic α-amino acids that are used in living systems and differs from the natural amino acids in that it has an α-methyl group rather than an α-H atom. In the crystal, an O—HO hydrogen bond is present between the acid and water molecules while extensive N—HO and O—HO hydrogen bonds link the components into a three-dimensional array.