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Mol-ecules of the title compound, [Zn(8)(C(6)F(5))(8)O(4)(C(4)H(10)O)(4)], are located on a special position of site symmetry [Formula: see text]. As a result, there is just one quarter-mol-ecule in the asymmetric unit. The title compound features a Zn(4)O(4) cube. Each Zn atom in the cube carries a pentafluorophenyl substituent. Each O atom is bonded to a further Zn atom, which is connected to a pentafluorophenyl substituent and the O atom of a diethyl ether mol-ecule. All ether C atoms are disordered over two sets of sites with a site occupation factor of 0.51 (2) for the major occupied site.
Molecules of the title compound, C20H14O2, show approximate C s symmetry with the approximate mirror plane perpendicular to the central ring. The torsion angles about the acyclic bonds are 30.05 (15) and 30.77 (15)° in one half compared to −36.62 (14) and −18.60 (15)° in the other half of the molecule. The central aromatic ring makes dihedral angles of 47.78 (4) and 51.68 (3)° with the two terminal rings.
The title compound, C14H20O5S·0.5H2O, crystallizes with two organic molecules and a solvent water molecule in the asymmetric unit. In both molecules, the hexapyranosyl rings adopt a slightly distorted chair conformation (5 C 2) with four substituents in equatorial positions and one substituent in an axial position. The main difference between the organic molecules is the dihedral angle between the phenyl ring and the best plane defined by the O—C1—C2—C3 atoms (r.m.s deviations = 0.003 and 0.043 Å) of the hexapyranosyl rings [47.4 (4) and 86.5 (4)°]. In the asymmetric unit, molecules are linked by two strong O—H[cdots, three dots, centered]O hydrogen bonds. In the crystal, the components are linked by a total of 10 distinct O—H[cdots, three dots, centered]O hydrogen bonds, resulting in the formation of a two-dimensional network parallel to the ab plane.
The title compound, C15H15BrO2, was synthesized by a Brønsted acid-catalysed domino electrocyclization-halogenation reaction. The five-membered ring is essentially planar (r.m.s. deviation 0.006 Å) and forms a dihedral angle of 72.7 (3)° with the attached phenyl ring. The six-membered heterocycle adopts a half-chair conformation. The crystal packing is stabilized by a C—H[cdots, three dots, centered]O contact.
The title compound, C(21)H(18)ClN, was synthesized by an enanti-oselective Brønsted acid-catalysed transfer hydrogenation reaction. The six-membered heterocycle adopts a half-chair conformation. It has the biphenyl residue in an axial position. The two rings of the biphenyl residue are almost coplanar [dihedral angle = 2.65 (9)°]. The crystal packing is stabilized by N-H⋯Cl hydrogen bonds, which connect the mol-ecules into chains running along the a axis.
The title compound, C25H20N4O2, is a ditopic ortho-hydroquinone-based bis(pyrazol-1-yl)methane ligand. The dihedral angles between the planes of the pyrazole rings and their attached phenyl rings are 17.4 (3) and 5.9 (4)°. The pyrazole rings make a dihedral angle of 87.84 (16)°. One of the two hydroxy groups forms an intramolecular hydrogen bond to the other hydroxy group, whereas the second is involved in an intermolecular O—H[cdots, three dots, centered]N hydrogen bond. As a result of these intermolecular hydrogen bonds, helical chains running along the b axis are formed.
The fused five- and six-membered rings in the title compound, C14H12N2O, are essentially planar, the largest deviation from the mean plane being 0.023 (2) Å. The dihedral angle between the benzimidazole mean plane and the phenyl ring is 68.50 (6)°. In the crystal, each molecule is linked to its symmetry equivalent created by a crystallographic inversion center by pairs of N—H[cdots, three dots, centered]O hydrogen bonds, forming inversion dimers.
In the mol-ecule of the title compound, C(12)H(12)BrN(3)O, the fused-ring system is essentially planar, the largest deviation from the mean plane being 0.0148 (3) Å. The two allyl groups are nearly perpendicular to the imidazo[4,5-b]pyridine plane [C-C-N-C torsion angles of 81.6 (4) and -77.2 (4)°] and point in the same direction. The planes through the atoms forming each allyl group are nearly perpendicular to the imidazo[4,5-b]pyridin-2-one system, as indicated by the dihedral angles between them of 80.8 (5) and 73.6 (5)°.
The two fused five- and six-membered rings building the molecule of the title compound, C13H10BrN3, are approximately planar, the largest deviation from the mean plane being 0.004 (2) Å. The dihedral angle between the imidazo[4,5-b]pyridine mean plane and that of the phenyl ring is 41.84 (11)°. The structure is held together by slipped π–π stacking between symmetry-related molecules, with an interplanar distance of 3.583 (1) Å and a centroid–centroid vector of 3.670 (2) Å.
The structure of the title compound, (C15H15N2O4)[AgI2], consists of an organic 4-[3-(isonicotinoyloxy)propoxycarbonyl]pyridinium cation which has a gauche–gauche (O/C/C/C—O/C/C/C or GG’) conformation and lies on a twofold rotation axis, which passes through the central C atom of the aliphatic chain, and an inorganic [AgI2]− anion. In the complex anion, the Ag+ cation is bound to two I− anions in a linear geometry. The anion was modelled assuming disorder around a crystallographic inversion centre near the location of the Ag+ cation. The crystal packing is stabilized by a strong intermolecular N—H[cdots, three dots, centered]N hydrogen bond, which links the cations into zigzag chains with graph-set notation C(16) running along the face diagonal of the ac plane. The N-bound H atom is disordered over two equally occupied symmetry-equivalent sites, so that the molecule has a pyridinium ring at one end and a pyridine ring at the other.
In the molecular structure of the title compound, C21H18N2O, the fused-ring system is essentially planar, the largest deviation from the mean plane being 0.0121 (9) Å. The O atom and adjacent C atom are located in Wyckoff position 4e on a twofold axis (0, y, 1/4). The two benzyl groups are almost perpendicular to the benzimidazole plane, but point in opposite directions. The dihedral angle between the benzimidazole mean plane and the phenyl ring is 81.95 (5)°, whereas that between the two benzyl groups is 60.96 (7)°.
The asymmetric unit of the title compound, C16H23ClN2O, comtains two independent molecules in which the fused-ring systems are essentially planar, the largest deviation from the mean plane of each molecule being 0.011 (2) Å and 0.016 (2) Å. The benzimidazole rings of the two molecules make a dihedral angle of 66.65 (7)°. The nonyl substituents are almost perpendicular to the benzimidazole planes [C—N—C—C tosrsion angles = 96.0 (3) and 81.0 (2)°]. In the crystal, each independent molecule forms an inversion dimer via a pair of N—H[cdots, three dots, centered]O hydrogen bonds. In one of the independent molecules, the terminal –CH2–CH3 group of the alkyl chain is disordered over two sets of sites with a refined occupancy ratio of 0.746 (7):0.254 (7).
The title compound, [Li4O4(C12H8BO)4(C4H10O)4], features a Li4O4 cube. Each Li atom in the cube is additionally coordinated by a diethyl ether molecule and each O atom in the cube carries a 9-oxa-10-boraanthracene residue. The crystal studied was a non-merohedral twin [twin law (-1 0 0 / 0 0 1 / 0 1 0); the contribution of the major twin component refined to 0.553 (3)] emulating apparent tetragonal symmetry, whereas the actual crystal system is just orthorhombic.
The crystal structure of the title compound, hexa-μ2-bromido-μ4-oxido-tetrakis[(diethyl ether)magnesium], [Mg4Br6O(C4H10O)4], determined from data measured at 173 K, differs from the previously known structure of diethyl ether magnesium oxybromide, which was determined from room-temperature data [Stucky & Rundle (1964 [triangle]). J. Am. Chem. Soc. 86, 4821–4825]. The title compound crystallizes in the tetragonal space group I An external file that holds a picture, illustration, etc. Object name is e-67-m1614-efi7.jpg, whereas the previously known structure crystallizes in a different tetragonal space group, namely P An external file that holds a picture, illustration, etc. Object name is e-67-m1614-efi7.jpg21 c. Both molecules have crystallographic An external file that holds a picture, illustration, etc. Object name is e-67-m1614-efi7.jpg symmetry and show almost identical geometric parameters for the Mg, Br and O atoms. The crystal of the title compound turned out to be a merohedral twin emulating a structure with apparent Laue symmetry 4/mmm, whereas the correct Laue group is just 4/m. The fractional contribution of the minor twin component converged to 0.462 (1).
The title compound, C26H18BrNO4, features a functionalized chromene. The cyclohexene ring adopts a sofa conformation and has the nitro group and the bromophenyl ring in an axial position. The ten atoms of the chromene moiety lie close to a common plane (r.m.s. deviation = 0.066 Å). The attached phenyl ring is twisted by 32.89 (10)° from the chromene plane. The crystal packing is stabilized by C—H[cdots, three dots, centered]O interactions.
The title molecule, C17H25N3O3, is built up from fused six- and five-membered rings linked to a –C10H21 chain. The fused-ring system is essentially planar, the largest deviation from the mean plane being 0.009 (2) Å. The chain is roughly perpendicular to this plane, making a dihedral angle of 79.5 (2)°. In the crystal, N—H[cdots, three dots, centered]O hydrogen bonds build infinite chains along [010]. There are channels in the structure containing disordered hexane. The contribution of this solvent to the scattering power was suppressed using the SQUEEZE option in PLATON [Spek (2009 [triangle]). Acta Cryst. D65, 148–155].
The title compound, C(19)H(14)ClNO(3)·0.2H(2)O, crystallizes with five mol-ecules and a disordered water mol-ecule in the asymmetric unit. Four of the five mol-ecules form hydrogen-bonded dimers via N-H⋯O hydrogen bonds towards another symmetry-independent mol-ecule, whereas the fifth mol-ecule forms a hydrogen-bonded dimer with its symmetry equivalent, also via N-H⋯O hydrogen bonds. The dihedral angle between the planes of the fused benzene ring and the five-membered ring to which it is attached is 79.45 (13), 49.00 (15), 72.49 (16), 81.91 (18) and 76.38 (16)° for the five mol-ecules in the asymmetric unit.
The structure of the title compound, C14H12N2O2 {systematic name: 2,2′-[hydrazinediylidenebis(methanylylidene)]diphenol}, has already been determined in the triclinic space group P An external file that holds a picture, illustration, etc. Object name is e-68-0o255-efi1.jpg with Z = 4 [El-Medani, Aboaly, Abdalla & Ramadan (2004 [triangle]). Spectrosc. Lett. 37, 619–632]. However, the correct space group should be P21/c with Z = 4. This structure is a new polymorph of the already known monoclinic polymorph of salicyladehyde azine, which crystallizes in space group P21/n with Z = 2. The benzene rings form a dihedral angle of 46.12 (9)°. Two intramolucular O—H[cdots, three dots, centered]N hydrogen bonds occur.