Crystal structure of 1,4-dieth-oxy-9,10-anthra-quinone.
ABSTRACT: The asymmetric unit of the title compound, C18H16O4, contains two crystallographically independent mol-ecules. The anthra-quinone ring systems are slightly bent with dihedral angles of 2.33?(8) and 13.31?(9)° between the two terminal benzene rings. In the crystal, the two independent mol-ecules adopt slipped-parallel ?-overlap with an average inter-planar distance of 3.45?Å, forming a dimer; the centroid-centroid distances of the ?-? inter-actions are 3.6659?(15)-3.8987?(15)?Å. The mol-ecules are also linked by C-H?O inter-actions, forming a tape structure along the a-axis direction. The crystal packing is characterized by a dimer-herringbone pattern.
Project description:In an attempt to brominate 1,4-diprop-oxy-9,10-anthra-quinone, a mixture of products, including the title compound, C14H7BrO4, was obtained. The mol-ecule is essentially planar (r.m.s. deviation = 0.029?Å) and two intra-molecular O-H?O hydrogen bonds occur. In the crystal, the mol-ecules are linked by weak C-H?O hydrogen bonds, Br?O contacts [3.240?(5)?Å], and ?-? stacking inter-actions [shortest centroid-centroid separation = 3.562?(4)?Å], generating a three-dimensional network.
Project description:In the title compound, C18H12O6, the anthra-quinone ring system is nearly planar [maximum deviation = 0.161?(3)?Å] and both acetate groups are located on the same side of the ring plane. A supra-molecular architecture arises in the crystal owing to ?-? stacking between parallel benzene rings of adjacent mol-ecules [centroid-centroid distance = 3.883?(4)?Å] and weak inter-molecular C-H?O hydrogen bonding.
Project description:The title compounds were obtained by deprotonation of 1,2,4-tri-hydroxy-anthra-quinone (purpurin) using sodium hydride followed by reaction with either 1-bromo-propane or 1-bromo-butane. 1,4-Dihy-droxy-2-propoxyanthra-quinone crystallizes as a 1:1 solvate from aceto-nitrile, C17H14O5·CH3CN. The anthra-quinone core of the mol-ecule is essentially planar and both hy-droxy groups participate in intra-molecular O-H?O (carbon-yl) hydrogen bonds. The propyl chain is angled slightly above the plane of the anthra-quinone moiety with a maximum deviation of 0.247?(2)?Å above the plane for the terminal carbon atom. In contrast, 2-but-oxy-1,4-di-hydroxy-anthra-quinone, C18H16O5, crystallizes from nitro-methane with two independent mol-ecules in the asymmetric unit. The anthra-quinone core of each independent mol-ecule is essentially planar and both hy-droxy groups on both mol-ecules participate in intra-molecular O-H?O(carbon-yl) hydrogen bonds. The butyl chain in one mol-ecule is also angled slightly above the plane of the anthra-quinone moiety, with a maximum deviation of 0.833?(5)?Å above the plane for the terminal carbon atom. In contrast, the butyl group on the second mol-ecule is twisted out of the plane of the anthra-quinone core with a torsion angle of 65.1?(3)°, resulting in a maximum deviation of 1.631?(5)?Å above the plane for the terminal carbon atom.
Project description:The asymmetric unit of the title compound, C(19)H(12)O(5), contains two independent mol-ecules, both slightly buckled along an axis passing through the C=O bonds of the anthraquinone ring system (r.m.s. deviation of non-H atoms = 0.082 and 0.148?Å): the benzene rings are twisted to each other by 4.3?(3)°in one mol-ecule and 10.6(3)° in the other. In both mol-ecules, the hy-droxy group forms an intra-molecular O-H?O hydrogen bond. The two independent mol-ecules inter-act by ?-? stacking with a centroid-centroid distance of 3.539?(2)?Å between hy-droxy-benzene rings of adjacent mol-ecules.
Project description:The asymmetric unit of the title compound, C(8)H(6)ClN(2)S(2), comprises two mol-ecules forming a dimer via ?-? stacking inter-actions [centroid-centroid distance = 3.634?(10)?Å] and intra-dimer S?S contacts [3.012?(4) and 3.158?(4)?Å] between the two mol-ecules in a cis-antarafacial arrangement.
Project description:The title compound, C17H12O4, was synthesized from the dye alizarin. The dihedral angle between the mean plane of the anthra-quinone ring system (r.m.s. deviation = 0.039?Å) and the dioxepine ring is 16.29?(8)°. In the crystal, the mol-ecules are linked by C-H?O hydrogen bonds, forming sheets lying parallel to the ab plane. The sheets are connected through ?-? and C=O?? inter-actions to generate a three-dimensional supra-molecular network. Hirshfeld surface analysis was used to investigate inter-molecular inter-actions in the solid-state: the most important contributions are from H?H (43.0%), H?O/O?H (27%), H?C/C?H (13.8%) and C?C (12.4%) contacts.
Project description:The asymmetric unit of the title co-crystal, C10H5BrO2·C14H8O4 [systematic name: 2-bromo-1,4-di-hydro-naphthalene-1,4-dione-1,8-dihy-droxy-9,10-di-hydro-anthracene-9,10-dione (1/1)], features one mol-ecule of each coformer. The 2-bromo-naphtho-quinone mol-ecule is almost planar [r.m.s deviation of the 13 non-H atoms = 0.060?Å, with the maximum deviations of 0.093?(1) and 0.099?(1)?Å being for the Br atom and a carbonyl-O atom, respectively]. The 1,8-di-hydroxy-anthra-quinone mol-ecule is planar (r.m.s. deviation for the 18 non-H atoms is 0.022?Å) and features two intra-molecular hy-droxy-O-H?O(carbon-yl) hydrogen bonds. Dimeric aggregates of 1,8-di-hydroxy-anthra-quinone mol-ecules assemble through weak inter-molecular hy-droxy-O-H?O(carbon-yl) hydrogen bonds. The mol-ecular packing comprises stacks of mol-ecules of 2-bromo-naphtho-quinone and dimeric assembles of 1,8-di-hydroxy-anthra-quinone with the shortest ?-? contact within a stack of 3.5760?(9)?Å occurring between the different rings of 2-bromo-naphtho-quinone mol-ecules. The analysis of the Hirshfeld surface reveals the importance of the inter-actions just indicated but, also the contribution of additional C-H?O contacts as well as C=O?? inter-actions to the mol-ecular packing.
Project description:The title compound, C28H22N2O8, possesses crystallographically imposed twofold symmetry, with the two central carbon atoms of the naphthalene unit lying on the rotation axis. The two benzoyl groups in the mol-ecule are twisted away from the attached naphthalene unit with a C-C-C=O torsion angle of 49.05?(15)° between the naphthalene unit and the carbonyl group. The dihedral angle between the naphthalene ring system and the benzene ring is 77.17?(5)°. In the crystal, pairs of C-H?O=C hydrogen bonds link the mol-ecules into a double-column structure along the c axis. The mol-ecules are further linked by C-H?O=N hydrogen bonds, forming a three-dimensional network. C-H?? inter-actions between the methyl-ene group and the naphthalene unit and ?-? inter-actions between the naphthalene ring systems [centroid-centroid distances of 3.7858?(7)-3.7860?(7)?Å] are also observed.
Project description:In the crystal structure of the title compound, C(15)H(20)N(2)O(3)S, the hy-droxy group is involved in the formation of O-H?N hydrogen bonds, which link two mol-ecules into a centrosymmetric dimer. Weak C-H?O hydrogen bonds further link these dimers into chains propagating along the a axis. The crystal packing exhibits ?-? inter-actions between the five- and six-membered rings of neighbouring mol-ecules [centroid-centroid distance = 3.819?(2)?Å] and short inter-molecular S?S contacts of 3.495?(1)?Å.
Project description:In the structure of the title compound, C(10)H(11)BrN(4), the plane of the substituted 1,2,3-triazole ring is tilted by 14.84?(10)° with respect to the mean plane of the pyridine ring. The pyridine and closest triazole N atoms adopt an anti arrangement which removes any lone pair-lone pair repulsions between the N atoms. This conformation is further stabilized by weak intermolecular C-H?N inter-actions. There are two mol-ecules in the unit cell, which form a centrosymmetric head-to-tail dimer. The dimers are stabilized through ?-? inter-actions [centroid-centroid distance = 3.733?(4)?Å and mean inter-planar distance = 3.806?(12)?Å] between the substituted 1,2,3-triazole ring and the pyridine rings in adjacent mol-ecules. Each dimer inter-acts with two neighbouring dimers above and below, forming a slipped stack of dimers through the crystal. The 3-bromo-propyl chain sits over the pyridine ring of a neighbouring mol-ecule and the triazole rings of nearby mol-ecules are adjacent.