2 Crystal structures of trans-diaqua(3-R-1,3,5,8,12-pentaazacyclotetradecane)copper(II) isophthalate hydrates (R = benzyl or pyridin-3-ylmethyl) By scripts.iucr.org Published On :: 2019-06-21 The asymmetric units of the title compounds, trans-diaqua(3-benzyl-1,3,5,8,12-pentaazacyclotetradecane-κ4N1,N5,N8,N12)copper(II) isophthalate monohydrate, [Cu(C16H29N5)(H2O)2](C8H4O4)·H2O, (I), and trans-diaqua[3-(pyridin-3-ylmethyl)-1,3,5,8,12-pentaazacyclotetradecane-κ4N1,N5,N8,N12]copper(II) isophthalate 0.9-hydrate, [Cu(C15H28N6)(H2O)2](C8H4O4)·0.9H2O, (II) consist of one diaqua macrocyclic cation, one dicarboxylate anion and uncoordinated water molecule(s). In each compound, the metal ion is coordinated by the four secondary N atoms of the macrocyclic ligand and the mutually trans O atoms of the water molecules in a tetragonally distorted octahedral geometry. The average equatorial Cu—N bond lengths are significantly shorter than the average axial Cu—O bond lengths [2.020 (9) versus 2.495 (12) Å and 2.015 (4) versus 2.507 (7) Å for (I) and (II), respectively]. The coordinated macrocyclic ligand in the cations of both compounds adopts the most energetically favorable trans-III conformation. In the crystals, the complex cations and counter-anions are connected via hydrogen-bonding interactions between the N—H groups of the macrocycles and the O—H groups of coordinated water molecules as the proton donors and the O atoms of the carboxylate as the proton acceptors. Additionally, as a result of O—H⋯O hydrogen bonding with the coordinated and water molecules of crystallization, the isophthalate dianions form layers lying parallel to the (overline{1}01) and (100) planes in (I) and (II), respectively. Full Article text
2 Syntheses, crystal structures, and comparisons of rare-earth oxyapatites Ca2RE8(SiO4)6O2 (RE = La, Nd, Sm, Eu, or Yb) and NaLa9(SiO4)6O2 By scripts.iucr.org Published On :: 2019-06-21 Six different rare-earth oxyapatites, including Ca2RE8(SiO4)6O2 (RE = La, Nd, Sm, Eu, or Yb) and NaLa9(SiO4)6O2, were synthesized using solution-based processes followed by cold pressing and sintering. The crystal structures of the synthesized oxyapatites were determined from powder X-ray diffraction (P-XRD) and their chemistries verified with electron probe microanalysis (EPMA). All the oxyapatites were isostructural within the hexagonal space group P63/m and showed similar unit-cell parameters. The isolated [SiO4]4− tetrahedra in each crystal are linked by the cations at the 4f and 6h sites occupied by RE3+ and Ca2+ in Ca2RE8(SiO4)6O2 or La3+ and Na+ in NaLa9(SiO4)6O2. The lattice parameters, cell volumes, and densities of the synthesized oxyapatites fit well to the trendlines calculated from literature values. Full Article text
2 Synthesis, detailed geometric analysis and bond-valence method evaluation of the strength of π-arene bonding of two isotypic cationic prehnitene tin(II) complexes: [{1,2,3,4-(CH3)4C6H2}2Sn2Cl2][MCl4]2 (M = Al and Ga) By scripts.iucr.org Published On :: 2019-06-25 From solutions of prehnitene and the ternary halides (SnCl)[MCl4] (M = Al, Ga) in chlorobenzene, the new cationic SnII–π-arene complexes catena-poly[[chloridoaluminate(III)]-tri-μ-chlorido-4':1κ2Cl,1:2κ4Cl-[(η6-1,2,3,4-tetramethylbenzene)tin(II)]-di-μ-chlorido-2:3κ4Cl-[(η6-1,2,3,4-tetramethylbenzene)tin(II)]-di-μ-chlorido-3:4κ4Cl-[chloridoaluminate(III)]-μ-chlorido-4:1'κ2Cl], [Al2Sn2Cl10(C10H14)2]n, (1) and catena-poly[[chloridogallate(III)]-tri-μ-chlorido-4':1κ2Cl,1:2κ4Cl-[(η6-1,2,3,4-tetramethylbenzene)tin(II)]-di-μ-chlorido-2:3κ4Cl-[(η6-1,2,3,4-tetramethylbenzene)tin(II)]-di-μ-chlorido-3:4κ4Cl-[chloridogallate(III)]-μ-chlorido-4:1'κ2Cl], [Ga2Sn2Cl10(C10H14)2]n, (2), were isolated. In these first main-group metal–prehnitene complexes, the distorted η6 arene π-bonding to the tin atoms of the Sn2Cl22+ moieties in the centre of [{1,2,3,4-(CH3)4C6H2}2Sn2Cl2][MCl4]2 repeating units (site symmetry overline{1}) is characterized by: (i) a significant ring slippage of ca 0.4 Å indicated by the dispersion of Sn—C distances [1: 2.881 (2)–3.216 (2) Å; 2: 2.891 (3)–3.214 (3) Å]; (ii) the non-methyl-substituted arene C atoms positioned closest to the SnII central atom; (iii) a pronounced tilt of the plane of the arene ligand against the plane of the central (Sn2Cl2)2+ four-membered ring species [1: 15.59 (11)°, 2: 15.69 (9)°]; (iv) metal–arene bonding of medium strength as illustrated by application of the bond-valence method in an indirect manner, defining the π-arene bonding interaction of the SnII central atoms as s(SnII—arene) = 2 − Σs(SnII—Cl), that gives s(SnII—arene) = 0.37 and 0.38 valence units for the aluminate and the gallate, respectively, indicating that comparatively strong main-group metal–arene bonding is present and in line with the expectation that [AlCl4]− is the slightly weaker coordinating anion as compared to [GaCl4]−. Full Article text
2 Crystal structure and the DFT and MEP study of 4-benzyl-2-[2-(4-fluorophenyl)-2-oxoethyl]-6-phenylpyridazin-3(2H)-one By scripts.iucr.org Published On :: 2019-06-21 The title pyridazin-3(2H)-one derivative, C25H19FN2O2, crystallizes with two independent molecules (A and B) in the asymmetric unit. In molecule A, the 4-fluorophenyl ring, the benzyl ring and the phenyl ring are inclined to the central pyridazine ring by 86.54 (11), 3.70 (9) and 84.857 (13)°, respectively. In molecule B, the corresponding dihedral angles are 86.80 (9), 10.47 (8) and 82.01 (10)°, respectively. In the crystal, the A molecules are linked by pairs of C—H⋯F hydrogen bonds, forming inversion dimers with an R22(28) ring motif. The dimers are linked by C—H⋯O hydrogen bonds and a C—H⋯π interaction, forming columns stacking along the a-axis direction. The B molecules are linked to each other in a similar manner and form columns separating the columns of A molecules. Full Article text
2 Crystal structure and Hirshfeld surface analysis of N-(2-chlorophenylcarbamothioyl)-4-fluorobenzamide and N-(4-bromophenylcarbamothioyl)-4-fluorobenzamide By scripts.iucr.org Published On :: 2019-06-21 The title compounds, C14H10ClFN2OS (1) and C14H10BrFN2OS (2), were synthesized by two-step reactions. The dihedral angles between the aromatic rings are 31.99 (3) and 9.17 (5)° for 1 and 2, respectively. Compound 1 features an intramolecular bifurcated N—H⋯(O,Cl) link due to the presence of the ortho-Cl atom on the benzene ring, whereas 2 features an intramolecular N—H⋯O hydrogen bond. In the crystal of 1, inversion dimers linked by pairs of N—H⋯S hydrogen bonds generate R22(8) loops. The extended structure of 2 features the same motif but an additional weak C—H⋯S interaction links the inversion dimers into [100] double columns. Hirshfeld surface analyses indicate that the most important contributors towards the crystal packing are H⋯H (26.6%), S⋯H/H.·S (13.8%) and Cl⋯H/H⋯Cl (9.5%) contacts for 1 and H⋯H (19.7%), C⋯H/H⋯C (14.8%) and Br⋯H/H⋯Br (12.4%) contacts for 2. Full Article text
2 Crystal structure of hexa-μ-chlorido-μ4-oxido-tetrakis{[1-(2-hydroxyethyl)-2-methyl-5-nitro-1H-imidazole-κN3]copper(II)} containing short NO2⋯NO2 contacts By scripts.iucr.org Published On :: 2019-06-25 The title tetranuclear copper complex, [Cu4Cl6O(C6H9N3O3)4] or [Cu4Cl6O(MET)4] [MET is 1-(2-hydroxyethyl)-2-methyl-5-nitro-1H-imidazole or metronidazole], contains a tetrahedral arrangement of copper(II) ions. Each copper atom is also linked to the other three copper atoms in the tetrahedron via bridging chloride ions. A fifth coordination position on each metal atom is occupied by a nitrogen atom of the monodentate MET ligand. The result is a distorted CuCl3NO trigonal–bipyramidal coordination polyhedron with the axial positions occupied by oxygen and nitrogen atoms. The extended structure displays O—H⋯O hydrogen bonding, as well as unusual short O⋯N interactions [2.775 (4) Å] between the nitro groups of adjacent clusters that are oriented perpendicular to each other. The scattering contribution of disordered water and methanol solvent molecules was removed using the SQUEEZE procedure [Spek (2015). Acta Cryst. C71, 9–16] in PLATON [Spek (2009). Acta Cryst. D65, 148–155]. Full Article text
2 (1R,2S,4r)-1,2,4-Triphenylcyclopentane-1,2-diol and (1R,2S,4r)-4-(2-methoxyphenyl)-1,2-diphenylcyclopentane-1,2-diol: application as initiators for ring-opening polymerization of ∊-caprolactone By scripts.iucr.org Published On :: 2019-06-21 Reductive cyclization of 1,3,5-triphenyl- and 3-(2-methoxyphenyl)-1,5-diphenylpentane-1,5-diones by zinc in acetic acid medium leads to the formation of 1,2,4-triphenylcyclopentane-1,2-diol [1,2,4-Ph3C5H5-1,2-(OH)2, C23H22O2, (I)] and 4-(2-methoxyphenyl)-1,2-diphenylcyclopentane-1,2-diol [4-(2-MeOC6H4)-1,2-Ph2C5H5-1,2-(OH)2, C24H24O3, (II)]. Their single crystals have been obtained by crystallization from a THF/hexane solvent mixture. Diols (I) and (II) crystallize in orthorhombic (Pbca) and triclinic (Poverline{1}) space groups, respectively, at 150 K. Their asymmetric units comprise one [in the case of (I)] and three [in the case of (II)] crystallographically independent molecules of the achiral (1R,2S,4r)-diol isomer. Each hydroxyl group is involved in one intramolecular and one intermolecular O—H⋯O hydrogen bond, forming one-dimensional chains. Compounds (I) and (II) have been used successfully as precatalyst activators for the ring-opening polymerization of ∊-caprolactone. Full Article text
2 Two new glaserite-type orthovanadates: Rb2KDy(VO4)2 and Cs1.52K1.48Gd(VO4)2 By scripts.iucr.org Published On :: 2019-06-21 The crystal structures of dirubidium potassium dysprosium bis(vanadate), Rb2KDy(VO4)2, and caesium potassium gadolinium bis(vanadate), Cs1.52K1.48Gd(VO4)2, were solved from single-crystal X-ray diffraction data. Both compounds, synthesized by the reactive flux method, crystallize in the space group Poverline{3}m1 with the glaserite structure type. VO4 tetrahedra are linked to DyO6 or GdO6 octahedra by common vertices to form sheets stacking along the c axis. The large twelve-coordinate Cs+ or Rb+ cations are sandwiched between these layers in tunnels along the a and b axes, while the K+ cations, surrounded by ten oxygen atoms, are localized in cavities. Full Article text
2 Crystal structure, spectroscopic characterization and Hirshfeld surface analysis of trans-diaqua[2,5-bis(pyridin-4-yl)-1,3,4-oxadiazole]dithiocyanatonickel(II) By scripts.iucr.org Published On :: 2019-06-21 The reaction of 2,5-bis(pyridin-4-yl)-1,3,4-oxadiazole (4-pox) and thiocyanate ions, used as co-ligand with nickel salt NiCl2·6H2O, produced the title complex, [Ni(NCS)2(C12H8N4O)2(H2O)2]. The NiII atom is located on an inversion centre and is octahedrally coordinated by four N atoms from two ligands and two pseudohalide ions, forming the equatorial plane. The axial positions are occupied by two O atoms of coordinated water molecules. In the crystal, the molecules are linked into a three-dimensional network through strong O—H⋯N hydrogen bonds. Hirshfeld surface analysis was used to investigate the intermolecular interactions in the crystal packing. Full Article text
2 Molecular and crystal structure of 5,9-dimethyl-5H-pyrano[3,2-c:5,6-c']bis[2,1-benzothiazin]-7(9H)-one 6,6,8,8-tetroxide dimethylformamide monosolvate By scripts.iucr.org Published On :: 2019-06-28 The title molecule crystallizes as a dimethylformamide monosolvate, C19H14N2O6S2·C3H7NO. The molecule was expected to adopt mirror symmetry but slightly different conformational characteristics of the condensed benzothiazine ring lead to point group symmetry 1. In the crystal, molecules form two types of stacking dimers with distances of 3.464 (2) Å and 3.528 (2) Å between π-systems. As a result, columns extending parallel to [100] are formed, which are connected to intermediate dimethylformamide solvent molecules by C—H⋯O interactions. Full Article text
2 Crystal structure of two N'-(1-phenylbenzylidene)-2-(thiophen-3-yl)acetohydrazides By scripts.iucr.org Published On :: 2019-07-02 The synthesis, spectroscopic data, crystal and molecular structures of two N'-(1-phenylbenzylidene)-2-(thiophen-3-yl)acetohydrazides, namely N'-[1-(4-hydroxyphenyl)benzylidene]-2-(thiophen-3-yl)acetohydrazide, C13H10N2O2S, (3a), and N'-[1-(4-methoxyphenyl)benzylidene]-2-(thiophen-3-yl)acetohydrazide, C14H14N2O2S, (3b), are described. Both compounds differ in the substituent at the para position of the phenyl ring: –OH for (3a) and –OCH3 for (3b). In (3a), the thiophene ring is disordered over two orientations with occupancies of 0.762 (3) and 0.238 (3). The configuration about the C=N bond is E. The thiophene and phenyl rings are inclined by 84.0 (3) and 87.0 (9)° for the major- and minor-occupancy disorder components in (3a), and by 85.89 (12)° in (3b). Although these dihedral angles are similar, the conformation of the linker between the two rings is different [the C—C—C—N torsion angle is −ac for (3a) and −sc for (3b), while the C6—C7—N9—N10 torsion angle is +ap for (3a) and −sp for (3b)]. A common feature in the crystal packing of (3a) and (3b) is the presence of N—H⋯O hydrogen bonds, resulting in the formation of chains of molecules running along the b-axis direction in the case of (3a), or inversion dimers for (3b). The most prominent contributions to the surface contacts are those in which H atoms are involved, as confirmed by an analysis of the Hirshfeld surface. Full Article text
2 Crystal structures of two CuII compounds: catena-poly[[chloridocopper(II)]-μ-N-[ethoxy(pyridin-2-yl)methylidene]-N'-[oxido(pyridin-3-yl)methylidene]hydrazine-κ4N,N',O:N''] and di-μ-chlorido-1:4κ2Cl:Cl-2:3κ2Cl:Cl-dichlorido-2κ By scripts.iucr.org Published On :: 2019-06-28 Two CuII complexes [Cu(C14H13N4O2)Cl]n, I, and [Cu4(C8H10NO2)4Cl4]n, II, have been synthesized. In the structure of the mononuclear complex I, each ligand is coordinated to two metal centers. The basal plane around the CuII cation is formed by one chloride anion, one oxygen atom, one imino and one pyridine nitrogen atom. The apical position of the distorted square-pyramidal geometry is occupied by a pyridine nitrogen atom from a neighbouring unit, leading to infinite one-dimensional polymeric chains along the b-axis direction. Each chain is connected to adjacent chains by intermolecular C—H⋯O and C—H⋯Cl interactions, leading to a three-dimensional network structure. The tetranuclear complex II lies about a crystallographic inversion centre and has one core in which two CuII metal centers are mutually interconnected via two enolato oxygen atoms while the other two CuII cations are linked by a chloride anion and an enolato oxygen. An open-cube structure is generated in which the two open-cube units, with seven vertices each, share a side composed of two CuII ions bridged by two enolato oxygen atoms acting in a μ3-mode. The CuII atoms in each of the two CuO3NCl units are connected by one μ2-O and two μ3-O atoms from deprotonated hydroxyl groups and one chloride anion to the three other CuII centres. Each of the pentacoordinated CuII cations has a distorted NO3Cl square-pyramidal environment. The CuII atoms in each of the two CuO2NCl2 units are connected by μ2-O and μ3-O atoms from deprotonated alcohol hydroxy groups and one chloride anion to two other CuII ions. Each of the pentacoordinated CuII cations has a distorted NO2Cl2 square-pyramidal environment. In the crystal, a series of intramolecular C—H⋯O and C—H⋯Cl hydrogen bonds are observed in each tetranuclear monomeric unit, which is connected to four tetranuclear monomeric units by intermolecular C—H⋯O hydrogen bonds, thus forming a planar two-dimensional structure in the (overline{1}01) plane. Full Article text
2 Crystal structure and Hirshfeld surface analysis of diiodido{N'-[(E)-(phenyl)(pyridin-2-yl-κN)methylidene]pyridine-2-carbohydrazide-κ2N',O}cadmium(II) By scripts.iucr.org Published On :: 2019-06-25 In each of the two independent molecules in the asymmetric unit of the title compound, [CdI2(C18H14N4O)], the N,O,N'-tridentate N'-[(E)-(phenyl)(pyridin-2-yl-κN)methylidene]pyridine-2-carbohydrazide ligand and two iodide anions form an I2N2O pentacoordination sphere, with a distorted square-pyramidal geometry, with an I atom in the apical position. Both molecules feature an intramolecular N—H⋯N hydrogen bond. In the crystal, weak aromatic π–π stacking interactions [centroid–centroid separation = 3.830 (2) Å] link the molecules into dimers. Full Article text
2 Crystal structure of (E)-N-cyclohexyl-2-(2-hydroxy-3-methylbenzylidene)hydrazine-1-carbothioamide By scripts.iucr.org Published On :: 2019-06-28 The asymmetric unit of the title compound, C15H21N3OS, comprises of two crystallographically independent molecules (A and B). Each molecule consists of a cyclohexane ring and a 2-hydroxy-3-methylbenzylidene ring bridged by a hydrazinecarbothioamine unit. Both molecules exhibit an E configuration with respect to the azomethine C=N bond. There is an intramolecular O—H⋯N hydrogen bond in each molecule forming an S(6) ring motif. The cyclohexane ring in each molecule has a chair conformation. The benzene ring is inclined to the mean plane of the cyclohexane ring by 47.75 (9)° in molecule A and 66.99 (9)° in molecule B. The mean plane of the cyclohexane ring is inclined to the mean plane of the thiourea moiety [N—C(=S)—N] by 55.69 (9) and 58.50 (8)° in molecules A and B, respectively. In the crystal, the A and B molecules are linked by N—H⋯S hydrogen bonds, forming `dimers'. The A molecules are further linked by a C—H⋯π interaction, hence linking the A–B units to form ribbons propagating along the b-axis direction. The conformation of a number of related cyclohexanehydrazinecarbothioamides are compared to that of the title compound. Full Article text
2 Crystal structure of bis[dihydrobis(pyrazol-1-yl)borato-κ2N2,N2'](1,10-phenanthroline-κ2N,N')zinc(II) By scripts.iucr.org Published On :: 2019-07-04 The asymmetric unit of the title compound, [Zn(C6H8N4B)2(C12H8N2)], comprises one half of a ZnII cation (site symmetry 2), one dihydrobis(pyrazol-1-yl)borate ligand in a general position, and one half of a phenanthroline ligand, the other half being completed by twofold rotation symmetry. The ZnII cation is coordinated in form of a slightly distorted octahedron by the N atoms of a phenanthroline ligand and by two pairs of N atoms of symmetry-related dihydrobis(pyrazol-1-yl)borate ligands. The discrete complexes are arranged into columns that elongate in the c-axis direction with a parallel alignment of the phenanthroline ligands, indicating weak π–π interactions. Full Article text
2 Crystal structure and Hirshfeld surface analysis of 2-[(2-oxo-2H-chromen-4-yl)oxy]acetic acid dimethyl sulfoxide monosolvate By scripts.iucr.org Published On :: 2019-07-09 The title compound, C11H8O5·(CH3)2SO, is a new coumarin derivative. The asymmetric unit contains two coumarin molecules (A and B) and two dimethylsulfoxide solvent molecules (A and B). The dihedral angle between the pyran and benzene rings in the chromene moiety is 3.56 (2)° for molecule A and 1.83 (2)° for molecule B. In molecule A, the dimethyl sulfoxide sulfur atom is disordered over two positions with a refined occupancy ratio of 0.782 (5):0.218 (5). In the crystal, molecules are linked by O—H⋯O hydrogen bonds, forming chains running along the c-axis direction. The chains are linked by C—H⋯O hydrogen bonds, forming layers parallel to the ac plane. In addition, there are also C—H⋯π and π–π interactions present within the layers. The intermolecular contacts in the crystal have been analysed using Hirshfeld surface analysis and two-dimensional fingerprint plots, which indicate that the most important contributions to the packing are from H⋯H (33.9%) and O⋯H/H⋯O (41.2%) contacts. Full Article text
2 Crystal structure of a low-spin poly[di-μ3-cyanido-di-μ2-cyanido-bis(μ2-2-ethylpyrazine)dicopper(I)iron(II)] By scripts.iucr.org Published On :: 2019-07-19 In the title metal–organic framework, [Fe(C6H8N2)2{Cu(CN)2}2]n, the low-spin FeII ion lies at an inversion centre and displays an elongated octahedral [FeN6] coordination environment. The axial positions are occupied by two symmetry-related bridging 2-ethylpyrazine ligands, while the equatorial positions are occupied by four N atoms of two pairs of symmetry-related cyanide groups. The CuI centre is coordinated by three cyanide carbon atoms and one N atom of a bridging 2-ethylpyrazine molecule, which form a tetrahedral coordination environment. Two neighbouring Cu atoms have a short Cu⋯Cu contact [2.4662 (7) Å] and their coordination tetrahedra are connected through a common edge between two C atoms of cyanide groups. Each Cu2(CN)2 unit, formed by two neighbouring Cu atoms bridged by two carbons from a pair of μ-CN groups, is connected to six FeII centres via two bridging 2-ethylpyrazine molecules and four cyanide groups, resulting in the formation of a polymeric three-dimensional metal–organic coordination framework. Full Article text
2 Crystal structure of 2-(methylamino)tropone By scripts.iucr.org Published On :: 2019-07-09 The title compound, 2-(methylamino)cyclohepta-2,4,6-trien-1-one, C8H9NO, crystallizes in the monoclinic space group P21/c, with three independent molecules in the asymmetric unit. The planarity of the molecules is indicated by planes fitted through the seven ring carbon atoms. Small deviations from the planes, with an extremal r.m.s. deviation of 0.0345 Å, are present. In complexes of transition metals with similar ligands, the large planar seven-membered aromatic rings have shown to improve the stability of the complex. Two types of hydrogen-bonding interactions, C—H⋯O and N—H⋯O, are observed, as well as bifurcation of these interactions. The N—H⋯O interactions link molecules to form infinite chains. The packing of molecules in the unit cell shows a pattern of overlapping aromatic rings, forming column-like formations. π–π interactions are observed between the overlapping aromatic rings at 3.4462 (19) Å from each other. Full Article text
2 (E)-6,6'-(Diazene-1,2-diyl)bis(1,10-phenanthrolin-5-ol) trichloromethane disolvate: a superconjugated ligand By scripts.iucr.org Published On :: 2019-07-23 Phenanthroline ligands are important metal-binding molecules which have been extensively researched for applications in both material science and medicinal chemistry. Azobenzene and its derivatives have received significant attention because of their ability to be reversibly switched between the E and Z forms and so could have applications in optical memory and logic devices or as molecular machines. Herein we report the formation and crystal structure of a highly unusual novel diazo-diphenanthroline compound, C24H14N6O2·2CHCl3. Full Article text
2 Crystal structure and Hirshfeld surface analysis of (E)-4-{[2,2-dichloro-1-(4-methoxyphenyl)ethenyl]diazenyl}benzonitrile By scripts.iucr.org Published On :: 2019-07-16 In the title compound, C16H11Cl2N3O, the 4-methoxy-substituted benzene ring makes a dihedral angle of 41.86 (9)° with the benzene ring of the benzonitrile group. In the crystal, molecules are linked into layers parallel to (020) by C—H⋯O contacts and face-to-face π–π stacking interactions [centroid–centroid distances = 3.9116 (14) and 3.9118 (14) Å] between symmetry-related aromatic rings along the a-axis direction. A Hirshfeld surface analysis indicates that the most important contributions to the crystal packing are from Cl⋯H/H⋯Cl (22.8%), H⋯H (21.4%), N⋯H/H⋯N (16.1%), C⋯H/H⋯C (14.7%) and C⋯C (9.1%) interactions. Full Article text
2 Crystal structure of catena-poly[[gold(I)-μ-cyanido-[diaquabis(2-phenylpyrazine)iron(II)]-μ-cyanido] dicyanidogold(I)] By scripts.iucr.org Published On :: 2019-07-12 In the title polymeric complex, {[Fe(CN)2(C10H8N2)2(H2O)2][Au(CN)2]}n, the FeII ion, which is located on a twofold rotation axis, has a slightly distorted FeN4O2 octahedral geometry. It is coordinated by two phenylpyrazine molecules, two water molecules and two dicyanoaurate anions, the Au atom also being located on a second twofold rotation axis. In the crystal, the coordinated dicyanoaurate anions bridge the FeII ions to form polymeric chains propagating along the b-axis direction. In the crystal, the chains are linked by Owater—H⋯Ndicyanoaurate anions hydrogen bonds and aurophillic interactions [Au⋯Au = 3.5661 (3) Å], forming layers parallel to the bc plane. The layers are linked by offset π–π stacking interactions [intercentroid distance = 3.643 (3) Å], forming a supramolecular metal–organic framework. Full Article text
2 Crystal structure, DFT study and Hirshfeld surface analysis of 1-nonyl-2,3-dihydro-1H-indole-2,3-dione By scripts.iucr.org Published On :: 2019-07-12 In the title molecule, C17H23NO2, the dihydroindole portion is planar (r.m.s. deviation = 0.0157 Å) and the nonyl substituent is in an `extended' conformation. In the crystal, the nonyl chains intercalate and the dihydroindoledione units are associated through C—H⋯O hydrogen bonds to form micellar blocks. Based on the Hirshfeld surface analysis, the most important intermolecular interaction is the H⋯H interaction. Full Article text
2 Crystal structure of poly[[[μ4-3-(1,2,4-triazol-4-yl)adamantane-1-carboxylato-κ5N1:N2:O1:O1,O1']silver(I)] dihydrate] By scripts.iucr.org Published On :: 2019-07-12 The heterobifunctional organic ligand, 3-(1,2,4-triazol-4-yl)adamantane-1-carboxylate (tr-ad-COO−), was employed for the synthesis of the title silver(I) coordination polymer, {[Ag(C13H16N3O2)]·2H2O}n, crystallizing in the rare orthorhombic C2221 space group. Alternation of the double μ2-1,2,4-triazole and μ2-η2:η1-COO− (chelating, bridging mode) bridges between AgI cations supports the formation of sinusoidal coordination chains. The AgI centers possess a distorted {N2O3} square-pyramidal arrangement with τ5 = 0.30. The angular organic linkers connect the chains into a tetragonal framework with small channels along the c-axis direction occupied by water molecules of crystallization, which are interlinked via O—H⋯O hydrogen bonds with carboxylate groups, leading to right- and left-handed helical dispositions. Full Article text
2 Syntheses, crystal structures and Hirshfeld surface analyses of (3aR,4S,7R,7aS)-2-(perfluoropyridin-4-yl)-3a,4,7,7a-tetrahydro-4,7-methanoisoindole-1,3-dione and (3aR,4S,7R,7aS)-2-[(perfluoropyridin-4-yl)oxy]-3a,4,7,7a- By scripts.iucr.org Published On :: 2019-07-12 The syntheses and crystal structures of the title compounds, C14H8F4N2O2 and C14H8F4N2O3, are reported. In each crystal, the packing is driven by C—H⋯F intertactions, along with a variety of C—H⋯O, C—O⋯π, and C—F⋯π contacts. Hirshfeld surface analysis was conducted to aid in the visualization of these various influences on the packing: they showed that the largest contributions to the surface contacts arise from H⋯F/F⋯H interactions, followed by H⋯H and O⋯H/H⋯O. Full Article text
2 An unexpected rhenium(IV)–rhenium(VII) salt: [Co(NH3)6]3[ReVIIO4][ReIVF6]4·6H2O By scripts.iucr.org Published On :: 2019-07-12 The title hydrated salt, tris[hexaamminecobalt(III)] tetraoxidorhenate(VII) tetrakis[hexafluoridorhenate(IV)] hexahydrate, arose unexpectedly due to possible contamination of the K2ReF6 starting material with KReO4. It consists of octahedral [Co(NH3)6]3+ cation (Co1 site symmetry 1), tetrahedral [ReVIIO4]− anions (Re site symmetry 1) and octahedral [ReIVF6]2− anions (Re site symmetries 1and overline{3}). The [ReF6]2− octahedral anions (mean Re—F = 1.834 Å), [Co(NH3)6]3+ octahedral cations (mean Co—N = 1.962 Å), and the [ReO4]− tetrahedral anion (mean Re—O = 1.719 Å) are slightly distorted. A network of N—H⋯F hydrogen bonds consolidates the structure. The crystal studied was refined as a two-component twin. Full Article text
2 Crystal structure of poly[[(μ3-hydroxido-κ3O:O:O)(μ3-selenato-κ3O1:O2:O3)tris[μ3-2-(1,2,4-triazol-4-yl)acetato-κ3N1:N2:O]tricopper(II)] dihydrate] By scripts.iucr.org Published On :: 2019-07-16 The title coordination polymer, {[Cu3(C4H4N3O9)3(SeO4)(OH)]·2H2O}n or ([Cu3(μ3-OH)(trgly)3(SeO4)]·2H2O), crystallizes in the monoclinic space group P21/c. The three independent Cu2+ cations adopt distorted square-pyramidal geometries with {O2N2+O} polyhedra. The three copper centres are bridged by a μ3-OH anion, leading to a triangular [Cu3(μ3-OH)] core. 2-(1,2,4-Triazol-4-yl)acetic acid (trgly-H) acts in a deprotonated form as a μ3-κ3N1:N2:O ligand. The three triazolyl groups bridge three copper centres of the hydroxo-cluster in an N1:N2 mode, thus supporting the triangular geometry. The [Cu3(μ3-OH)(tr)3] clusters serve as secondary building units (SBUs). Each SBU can be regarded as a six-connected node, which is linked to six neighbouring triangles through carboxylate groups, generating a two-dimensional uninodal (3,6) coordination network. The selenate anion is bound in a μ3-κ3O1:O2:O3 fashion to the trinuclear copper platform. The [Cu3(OH)(trgly)3(SeO4)] coordination layers and guest water molecules are linked together by numerous O—H⋯O and C—H⋯O hydrogen bonds, leading to a three-dimensional structure. Full Article text
2 Crystal structure, Hirshfeld surface analysis and corrosion inhibition study of 3,6-bis(pyridin-2-yl)-4-{[(3aS,5S,5aR,8aR,8bS)-2,2,7,7-tetramethyltetrahydro-5H-bis[1,3]dioxolo[4,5-b:4',5'-d]pyran-5-yl)methoxy]meth By scripts.iucr.org Published On :: 2019-07-12 In the title compound, C27H30N4O6·H2O, the two dioxolo rings are in envelope conformations, while the pyran ring is in a twisted-boat conformation. The pyradizine ring is oriented at dihedral angles of 9.23 (6) and 12.98 (9)° with respect to the pyridine rings, while the dihedral angle between the two pyridine rings is 13.45 (10)°. In the crystal, O—Hwater⋯Opyran, O—Hwater⋯Omethoxymethyl and O—Hwater⋯Npyridazine hydrogen bonds link the molecules into chains along [010]. In addition, weak C—Hdioxolo⋯Odioxolo hydrogen bonds and a weak C—Hmethoxymethyl⋯π interaction complete the three-dimensional structure. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H⋯H (55.7%), H⋯C/C⋯H (14.6%), H⋯O/O⋯H (14.5%) and H⋯N/N⋯H (9.6%) interactions. Hydrogen-bonding and van der Waals interactions are the dominant interactions in the crystal packing. Electrochemical measurements are also reported. Full Article text
2 Crystal structure of (15,20-bis(2,3,4,5,6-pentafluorophenyl)-5,10-{(pyridine-3,5-diyl)bis[(sulfanediylmethylene)[1,1'-biphenyl]-4',2-diyl]}porphyrinato)nickel(II) dichloro By scripts.iucr.org Published On :: 2019-07-12 The crystal structure of the title compound, [Ni(C63H31F10N5S2)]·xCH2Cl2 (x > 1/2), consists of Ni–porphyrin complexes that are located in general positions and dichloromethane solvent molecules that are disordered around centers of inversion. The NiII ions are in a square-pyramidal (CN5) coordination, with four porphyrin N atoms in the equatorial and a pyridine N atom in the apical position and are shifted out of the porphyrine N4 plane towards the coordinating pyridine N atom. The pyridine substituent is not exactly perpendicular to the N4 plane with an angle of intersection between the planes planes of 80.48 (6)°. The dichloromethane solvent molecules are hydrogen bonded to one of the four porphyrine N atoms. Two complexes are linked into dimers by two symmetry-equivalent C—H⋯S hydrogen bonds. These dimers are closely packed, leading to cavities in which additional dichloromethane solvent molecules are embedded. These solvent molecules are disordered and because no reasonable split model was found, the data were corrected for disordered solvent using the PLATON SQUEEZE routine [Spek (2015). Acta Cryst. C71, 9–18]. Full Article text
2 Crystal structure and Hirshfeld surface analysis of (E)-3-[(4-chlorobenzylidene)amino]-5-phenylthiazolidin-2-iminium bromide By scripts.iucr.org Published On :: 2019-07-12 The title salt, C16H15ClN3S+·Br−, is isotypic with (E)-3-[(4-fluorobenzylidene)amino]-5-phenylthiazolidin-2-iminium bromide [Khalilov et al. (2019). Acta Cryst. E75, 662–666]. In the cation of the title salt, the atoms of the phenyl ring attached to the central thiazolidine ring and the atom joining the thiazolidine ring to the benzene ring are disordered over two sets of sites with occupancies of 0.570 (3) and 0.430 (3). The major and minor components of the disordered thiazolidine ring adopt slightly distorted envelope conformations, with the C atom bearing the phenyl ring as the flap atom. In the crystal, centrosymmetrically related cations and anions are linked into dimeric units via N—H⋯Br hydrogen bonds, which are further connected by weak C—H⋯Br contacts into chains parallel to the a axis. Furthermore, not existing in the earlier report of (E)-3-[(4-fluorobenzylidene)amino]-5-phenylthiazolidin-2-iminium bromide, C—H⋯π interactions and π–π stacking interactions [centroid-to-centroid distance = 3.897 (2) Å] between the major components of the disordered phenyl ring contribute to the stabilization of the molecular packing. Hirshfeld surface analysis and two-dimensional fingerprint plots indicate that the most important contributions for the crystal packing are from H⋯H (30.5%), Br⋯H/H⋯Br (21.2%), C⋯H/H⋯C (19.2%), Cl⋯H/H⋯Cl (13.0%) and S⋯H/H⋯S (5.0%) interactions. Full Article text
2 Crystal structures of an imidazo[1,5-a]pyridinium-based ligand and its (C13H12N3)2[CdI4] hybrid salt By scripts.iucr.org Published On :: 2019-07-19 The monocation product of the oxidative condensation–cyclization between two molecules of pyridine-2-carbaldehyde and one molecule of CH3NH2·HCl in methanol, 2-methyl-3-(pyridin-2-yl)imidazo[1,5-a]pyridinium, was isolated in the presence of metal ions as bis[2-methyl-3-(pyridin-2-yl)imidazo[1,5-a]pyridin-2-ium] tetraiodocadmate, (C13H12N3)2[CdI4], (I), and the mixed chloride/nitrate salt, bis[2-methyl-3-(pyridin-2-yl)imidazo[1,5-a]pyridin-2-ium] 1.5-chloride 0.5-nitrate trihydrate, 2C13H12N3+·1.5Cl−·0.5NO3−·3H2O, (II). Hybrid salt (I) crystallizes in the space group P21/n with two [L]2[CdI4] molecules in the asymmetric unit related by pseudosymmetry. In the crystal of (I), layers of organic cations and of tetrahalometallate anions are stacked parallel to the ab plane. Antiparallel L+ cations disposed in a herring-bone pattern form π-bonded chains through aromatic stacking. In the inorganic layer, adjacent tetrahedral CdI4 units have no connectivity but demonstrate close packing of iodide anions. In the crystal lattice of (II), the cations are arranged in stacks propagating along the a axis; the one-dimensional hydrogen-bonded polymer built of chloride ions and water molecules runs parallel to a column of stacked cations. Full Article text
2 Crystal structures and Hirshfeld surface analyses of the two isotypic compounds (E)-1-(4-bromophenyl)-2-[2,2-dichloro-1-(4-nitrophenyl)ethenyl]diazene and (E)-1-(4-chlorophenyl)-2-[2,2-dichloro-1-(4-ni By scripts.iucr.org Published On :: 2019-07-19 In the two isotypic title compounds, C14H8BrCl2N3O2, (I), and C14H8Cl3N3O2, (II), the substitution of one of the phenyl rings is different [Br for (I) and Cl for (II)]. Aromatic rings form dihedral angles of 60.9 (2) and 64.1 (2)°, respectively. Molecules are linked through weak X⋯Cl contacts [X = Br for (I) and Cl for (II)], C—H⋯Cl and C—Cl⋯π interactions into sheets parallel to the ab plane. Additional van der Waals interactions consolidate the three-dimensional packing. Hirshfeld surface analysis of the crystal structures indicates that the most important contributions for the crystal packing for (I) are from C⋯H/H⋯C (16.1%), O⋯H/H⋯O (13.1%), Cl⋯H/H⋯Cl (12.7%), H⋯H (11.4%), Br⋯H/H⋯Br (8.9%), N⋯H/H⋯N (6.9%) and Cl⋯C/C⋯Cl (6.6%) interactions, and for (II), from Cl⋯H / H⋯Cl (21.9%), C⋯H/H⋯C (15.3%), O⋯H/H⋯O (13.4%), H⋯H (11.5%), Cl⋯C/C⋯Cl (8.3%), N⋯H/H⋯N (7.0%) and Cl⋯Cl (5.9%) interactions. The crystal of (I) studied was refined as an inversion twin, the ratio of components being 0.9917 (12):0.0083 (12). Full Article text
2 Crystal structure and Hirshfeld surface analysis of 2,5-dibromoterephthalic acid ethylene glycol monosolvate By scripts.iucr.org Published On :: 2019-07-23 The title compound, C8H4Br2O4·C2H6O2, crystallizes with one-half of a 2,5-dibromoterephthalic acid (H2Br2tp) molecule and one-half of an ethylene glycol (EG) molecule in the the asymmetric unit. The whole molecules are generated by application of inversion symmetry. The H2Br2tp molecule is not planar, with the dibromobenzene ring system inclined by a dihedral angle of 18.62 (3)° to the carboxylic group. In the crystal, the H2Br2tp and EG molecules are linked into sheets propagating parallel to (overline{1}01) through O—H⋯O hydrogen bonds, thereby forming R44 (12) and R44 (28) graph-set motifs. Br⋯O and weak π–π stacking interactions are also observed. Hirshfeld surface analysis was used to confirm the existence of these interactions. Full Article text
2 2-Methyl-4-(4-nitrophenyl)but-3-yn-2-ol: crystal structure, Hirshfeld surface analysis and computational chemistry study By scripts.iucr.org Published On :: 2019-07-23 The di-substituted acetylene residue in the title compound, C11H11NO3, is capped at either end by di-methylhydroxy and 4-nitrobenzene groups; the nitro substituent is close to co-planar with the ring to which it is attached [dihedral angle = 9.4 (3)°]. The most prominent feature of the molecular packing is the formation, via hydroxy-O—H⋯O(hydroxy) hydrogen bonds, of hexameric clusters about a site of symmetry overline{3}. The aggregates are sustained by 12-membered {⋯OH}6 synthons and have the shape of a flattened chair. The clusters are connected into a three-dimensional architecture by benzene-C—H⋯O(nitro) interactions, involving both nitro-O atoms. The aforementioned interactions are readily identified in the calculated Hirshfeld surface. Computational chemistry indicates there is a significant energy, primarily electrostatic in nature, associated with the hydroxy-O—H⋯O(hydroxy) hydrogen bonds. Dispersion forces are more important in the other identified but, weaker intermolecular contacts. Full Article text
2 Crystal structure of tetra-μ-acetato-bis[(5-amino-2-methylsulfanyl-1,3,4-thiadiazole-κN1)copper(II)] By scripts.iucr.org Published On :: 2019-07-23 The reaction of 2-methylthio-5-amino-1,3,4-thiadiazole (Me-SNTD; C3H5N3S2) with copper(II) acetate monohydrate [Cu(OAc)2·H2O; C4H8CuO5] resulted in the formation of the title binuclear compound, [Cu2(C2H3O2)4(C3H5N3S2)2] or [Cu2(OAc)4(Me-SNTD)2]. The structure has triclinic (P overline{1}) symmetry with a crystallographic inversion centre located at the midpoint of the line connecting the Cu atoms in the dimer. These two Cu atoms of the dimer [Cu⋯Cu = 2.6727 (6) Å] are held together by four carboxylate groups. Each Cu atom is further coordinated to the N atom of an Me-SNTD molecule and exhibits a Jahn–Teller-distorted octahedral geometry. The dimers are connected into infinite chains by hydrogen bonds between the NH (Me-SNTD) and the carboxylate groups of neighbouring molecules, generating an R22(12) ring motif. The molecules are further linked by C—H⋯π interactions between the thiadiazole rings and the methyl groups of the acetate units. Full Article text
2 Syntheses and crystal structures of a new family of hybrid perovskites: C5H14N2·ABr3·0.5H2O (A = K, Rb, Cs) By scripts.iucr.org Published On :: 2019-07-26 The syntheses and crystal structures of three hybrid perovskites, viz. poly[1-methylpiperizine-1,4-diium [tri-μ-bromido-potassium] hemihydrate], {(C5H14N2)[KBr3]·0.5H2O}n, (I), poly[1-methylpiperizine-1,4-diium [tri-μ-bromido-rubidium] hemihydrate], {(C5H14N2)[RbBr3]·0.5H2O}n, (II), and poly[1-methylpiperizine-1,4-diium [tri-μ-bromido-caesium] hemihydrate], {(C5H14N2)[CsBr3]·0.5H2O}n, (III), are described. These isostructural (space group Amm2) phases contain a three-dimensional, corner-sharing network of distorted ABr6 octahedra (A = K, Rb, Cs) with the same topology as the classical perovskite structure. The doubly protonated C5H14N22+ cations occupy interstices bounded by eight octahedra and the water molecules lie in square sites bounded by four octahedra. N—H⋯Br, N—H⋯(Br,Br), N—H⋯O and O—H⋯Br hydrogen bonds consolidate the structures. Full Article text
2 Syntheses and structures of piperazin-1-ium ABr2 (A = Cs or Rb): hybrid solids containing `curtain wall' layers of face- and edge-sharing ABr6 trigonal prisms By scripts.iucr.org Published On :: 2019-07-26 The isostructural title compounds, poly[piperazin-1-ium [di-μ-bromido-caesium]], {(C4H11N2)[CsBr2]}n, and poly[piperazin-1-ium [di-μ-bromido-rubidium]], {(C4H11N2)[RbBr2]}n, contain singly-protonated piperazin-1-ium cations and unusual ABr6 (A = Cs or Rb) trigonal prisms. The prisms are linked into a distinctive `curtain wall' arrangement propagating in the (010) plane by face and edge sharing. In each case, a network of N—H⋯N, N—H⋯Br and N—H⋯(Br,Br) hydrogen bonds consolidates the structure. Full Article text
2 Palladium(II) complexes of a bridging amine bis(phenolate) ligand featuring κ2 and κ3 coordination modes By scripts.iucr.org Published On :: 2019-07-26 Bidentate and tridentate coordination of a 2,4-di-tert-butyl-substituted bridging amine bis(phenolate) ligand to a palladium(II) center are observed within the same crystal structure, namely dichlorido({6,6'-[(ethane-1,2-diylbis(methylazanediyl)]bis(methylene)}bis(2,4-di-tert-butylphenol))palladium(II) chlorido(2,4-di-tert-butyl-6-{[(2-{[(3,5-di-tert-butyl-2-hydroxyphenyl)methyl](methyl)amino}ethyl)(methyl)amino]methyl}phenolato)palladium(II) methanol 1.685-solvate 0.315-hydrate, [PdCl2(C34H56N2O2)][PdCl(C34H55N2O2)]·1.685CH3OH·0.315H2O. Both complexes exhibit a square-planar geometry, with unbound phenol moieties participating in intermolecular hydrogen bonding with co-crystallized water and methanol. The presence of both κ2 and κ3 coordination modes arising from the same solution suggest a dynamic process in which phenol donors may coordinate or dissociate from the metal center, and offers insight into catalyst speciation throughout Pd-mediated processes. The unit cell contains dichlorido({6,6'-[(ethane-1,2-diylbis(methylazanediyl)]bis(methylene)}bis(2,4-di-tert-butylphenol))palladium(II), {(L2)PdCl2}, and chlorido(2,4-di-tert-butyl-6-{[(2-{[(3,5-di-tert-butyl-2-hydroxyphenyl)methyl](methyl)amino}ethyl)(methyl)amino]methyl}phenolato)palladium(II), {(L2X)PdCl}, molecules as well as fractional water and methanol solvent molecules. Full Article text
2 Crystal structures of two isomeric 2-aryl-3-phenyl-1,3-thiazepan-4-ones By scripts.iucr.org Published On :: 2019-07-26 The crystal of 6-(3-nitrophenyl)-7-phenyl-5-thia-7-azaspiro[2.6]nonan-8-one (1), C19H18N2O3S, has monoclinic (P21/n) symmetry while that of its isomer 6-(4-nitrophenyl)-7-phenyl-5-thia-7-azaspiro[2.6]nonan-8-one (2), has orthorhombic (Pca21) symmetry: compound 1 has two molecules, A and B, in the asymmetric unit while 2 has one. In all three molecules, the seven-membered thiazepan ring exhibits a chair conformation with Q2 and Q3 values (Å) of 0.521 (3), 0.735 (3) and 0.485 (3), 0.749 (3) in 1 and 0.517 (5), 0.699 (5) in 2. In each structure, the phenyl rings attached to adjacent atoms of the thiazepan ring have interplanar angles ranging between 41 and 47°. Except for the nitro groups, the three molecules have similar conformations when overlayed in pairs. Both crystal structures are consolidated by C—H⋯O hydrogen bonds. Full Article text
2 Crystal structure and chemistry of tricadmium digermanium tetraarsenide, Cd3Ge2As4 By scripts.iucr.org Published On :: 2019-08-02 A cadmium germanium arsenide compound, Cd3Ge2As4, was synthesized using a double-containment fused quartz ampoule method within a rocking furnace and a melt-quench technique. The crystal structure was determined from single-crystal X-ray diffraction (SC-XRD), scanning and transmission electron microscopies (i.e. SEM, STEM, and TEM), and selected area diffraction (SAD) and confirmed with electron backscatter diffraction (EBSD). The chemistry was verified with electron energy loss spectroscopy (EELS). Full Article text
2 Synthesis and structure of 2,4,6-tricyclobutyl-1,3,5-trioxane By scripts.iucr.org Published On :: 2019-10-03 The synthesis and structure of 2,4,6,-tricyclobutyl-1,3,5-trioxane, C15H24O3 1, is described. It was formed in 39% yield during the work-up of the Swern oxidation of cyclobutylmethanol and may serve as a stable precursor of the cyclobutane carbaldehyde. The molecule of 1 occupies a special position (3.m) located at the center of its 1,3,5-trioxane ring. The latter is in a chair conformation, with the symmetry-independent O and C atoms deviating by 0.651 (4) Å from the least-squares plane of the other atoms of the trioxane ring. All three cyclobutane substituents, which have a butterfly conformation with an angle between the two planes of 25.7 (3)°, are in the cis conformation relative to the 1,3,5-trioxane ring. Intermolecular C—H⋯O interactions between the 1,3,5-trioxane rings consolidate the crystal structure, forming stacks along the c-axis direction. The crystal studied was refined a as a racemic twin. Full Article text
2 Crystal structure and Hirshfeld surface analysis of a new dithioglycoluril: 1,4-bis(4-methoxyphenyl)-3a-methyltetrahydroimidazo[4,5-d]imidazole-2,5(1H,3H)-dithione By scripts.iucr.org Published On :: 2019-08-06 In the title dithioglycoluril derivative, C19H20N4O3S2, there is a difference in the torsion angles between the thioimidazole moiety and the methoxyphenyl groups on either side of the molecule [C—N—Car—Car = 116.9 (2) and −86.1 (3)°, respectively]. The N—C—N bond angle on one side of the dithioglycoluril moiety is slightly smaller compared to that on the opposite side, [110.9 (2)° cf. 112.0 (2)°], probably as a result of the steric effect of the methyl group. In the crystal, N—H⋯S hydrogen bonds link adjacent molecules to form chains propagating along the c-axis direction. The chains are linked by C—H⋯S hydrogen bonds, forming layers parallel to the bc plane. The layers are then linked by C—H⋯π interactions, leading to the formation of a three-dimensional supramolecular network. Hirshfeld surface analysis and two-dimensional fingerprint plots were used to investigate the molecular interactions in the crystal. Full Article text
2 Crystal structure and Hirshfeld surface analysis of bis(benzoato-κ2O,O')[bis(pyridin-2-yl-κN)amine]nickel(II) By scripts.iucr.org Published On :: 2019-08-13 A new mononuclear NiII complex with bis(pyridin-2-yl)amine (dpyam) and benzoate (benz), [Ni(C7H5O2)2(C10H9N3)], crystallizes in the monoclinic space group P21/c. The NiII ion adopts a cis-distorted octahedral geometry with an [NiN2O4] chromophore. In the crystal, the complex molecules are linked together into a one-dimensional chain by symmetry-related π–π stacking interactions [centroid-to-centroid distance = 3.7257 (17) Å], along with N—H⋯O and C—H⋯O hydrogen bonds. The crystal packing is further stabilized by C—H⋯π interactions, which were investigated by Hirshfeld surface analysis. Full Article text
2 The first crystal structure of the pyrrolo[1,2-c]oxazole ring system By scripts.iucr.org Published On :: 2019-08-23 The title compound, C7H4F3NO2, 3-trifluoromethyl-1H-pyrrolo[1,2-c]oxazol-1-one, is the first crystal structure of the pyrrolo[1,2-c]oxazole ring system: the fused ring system is almost planar (r.m.s. deviation = 0.006 Å). In the crystal, weak C—H⋯O and C—H⋯F hydrogen bonds link the molecules into [001] chains and π–π stacking interactions consolidate the structure. Full Article text
2 Crystal structure, Hirshfeld surface analysis and interaction energy and DFT studies of 4-[(prop-2-en-1-yloxy)methyl]-3,6-bis(pyridin-2-yl)pyridazine By scripts.iucr.org Published On :: 2019-08-20 The title compound, C18H16N4O, consists of a 3,6-bis(pyridin-2-yl)pyridazine moiety linked to a 4-[(prop-2-en-1-yloxy)methyl] group. The pyridine-2-yl rings are oriented at a dihedral angle of 17.34 (4)° and are rotated slightly out of the plane of the pyridazine ring. In the crystal, C—HPyrd⋯NPyrdz (Pyrd = pyridine and Pyrdz = pyridazine) hydrogen bonds and C—HPrpoxy⋯π (Prpoxy = prop-2-en-1-yloxy) interactions link the molecules, forming deeply corrugated layers approximately parallel to the bc plane and stacked along the a-axis direction. Hirshfeld surface analysis indicates that the most important contributions for the crystal packing are from H⋯H (48.5%), H⋯C/C⋯H (26.0%) and H⋯N/N⋯H (17.1%) contacts, hydrogen bonding and van der Waals interactions being the dominant interactions in the crystal packing. Computational chemistry indicates that in the crystal, the C—HPyrd⋯NPyrdz hydrogen-bond energy is 64.3 kJ mol−1. Density functional theory (DFT) optimized structures at the B3LYP/6–311 G(d,p) level are compared with the experimentally determined molecular structure in the solid state. The HOMO–LUMO behaviour was elucidated to determine the energy gap. Full Article text
2 Syntheses and crystal structures of 2-methyl-1,1,2,3,3-pentaphenyl-2-silapropane and 2-methyl-1,1,3,3-tetraphenyl-2-silapropan-2-ol By scripts.iucr.org Published On :: 2019-08-23 The sterically hindered silicon compound 2-methyl-1,1,2,3,3-pentaphenyl-2-silapropane, C33H30Si (I), was prepared via the reaction of two equivalents of diphenylmethyllithium (benzhydryllithium) and dichloromethylphenylsilane. This bisbenzhydryl-substituted silicon compound was then reacted with trifluoromethanesulfonic acid, followed by hydrolysis with water to give the silanol 2-methyl-1,1,3,3-tetraphenyl-2-silapropan-2-ol, C27H26OSi (II). Key geometric features for I are the Si—C bond lengths that range from 1.867 (2) to 1.914 (2) Å and a τ4 descriptor for fourfold coordination around the Si atom of 0.97 (indicating a nearly perfect tetrahedron). Key geometric features for compound II include Si—C bond lengths that range from 1.835 (4) to 1.905 (3) Å, a Si—O bond length of 1.665 (3) Å, and a τ4 descriptor for fourfold coordination around the Si atom of 0.96. In compound II, there is an intramolecular C—H⋯O hydrogen bond present. In the crystal of I, molecules are linked by two pairs of C—H⋯π interactions, forming dimers that are linked into ribbons propagating along the b-axis direction. In the crystal of II, molecules are linked by C—H⋯π and O—H⋯π interactions that result in the formation of ribbons that run along the a-axis direction. Full Article text
2 Crystal structure of (E)-3-(2-hydroxy-4-methylphenyl)-1-(2,4,6-trimethoxyphenyl)prop-2-en-1-one By scripts.iucr.org Published On :: 2019-08-30 The title chalcone derivative, C19H20O5, adopts a trans configuration with respect to the olefinic C=C double bond. The 2-hydroxy-4-methylphenyl ring is coplanar with the attached enone bridge [torsion angle = −179.96 (14)°], where this plane is nearly perpendicular to the 2,4,6-trimethoxyphenyl ring [dihedral angle = 75.81 (8)°]. In the crystal, molecules are linked into chains propagating along [010] by an O—H⋯O hydrogen bond. These chains are further connected into centrosymmetric dimer chains via weak C—H⋯O interactions. The conformations of related chalcone derivatives are surveyed and all of these structures adopt a skeleton with two almost orthogonal aromatic rings. Full Article text
2 Absolute structure of (3aS,5S,7aS,7bS,9aR,10R,12aR,12bS)-7b-hydroxy-4,4,7a,9a,12a-pentamethyl-10-[(2'R)-6-methylheptan-2-yl]-2,8,9-trioxooctadecahydrobenzo[d]indeno[4,5-b]azepin-5-yl acetate from 62-year-old By scripts.iucr.org Published On :: 2019-08-23 The structure of the title compound, C32H51NO6, was determined from 62-year-old crystals at room temperature and refined with 100 K data in a monoclinic (C2) space group. This compound with a triterpenoid structure, now confirmed by this study, played an important role in the determination of the structure of lanosterol. The molecules pack in linear O—H⋯O hydrogen-bonded chains along the short axis (b), while parallel chains display weak van der Waals interactions that explain the needle-shaped crystal morphology. The structure exhibits disorder of the flexible methylheptane chain at one end of the main molecule with a small void around it. Crystals of the compounds were resistant to data collection for decades with the available cameras and Mo Kα radiation single-crystal diffractometer in our laboratory until a new instrument with Cu Kα radiation operating at 100 K allowed the structure to be solved and refined. Full Article text
2 Synthesis, characterization, crystal structure and supramolecularity of ethyl (E)-2-cyano-3-(3-methylthiophen-2-yl)acrylate and a new polymorph of ethyl (E)-2-cyano-3-(thiophen-2-yl)acrylate By scripts.iucr.org Published On :: 2019-08-23 The synthesis, crystal structure and structural motif of two thiophene-based cyanoacrylate derivatives, namely, ethyl (E)-2-cyano-3-(3-methylthiophen-2-yl)acrylate (1), C11H11NO2S, and ethyl (E)-2-cyano-3-(thiophen-2-yl)acrylate (2), C10H9NO2S, are reported. Derivative 1 crystallized with two independent molecules in the asymmetric unit, and derivative 2 represents a new monoclinic (C2/m) polymorph. The molecular conformations of 1 and the two polymorphs of 2 are very similar, as all non-H atoms are planar except for the methyl of the ethyl groups. The intermolecular interactions and crystal packing of 1 and 2 are described and compared with that of the reported monoclinic (C2/m) polymorph of derivative 2 [Castro Agudelo et al. (2017). Acta Cryst. E73, 1287–1289]. Full Article text
2 Crystal structure of tetramethylammonium 1,1,7,7-tetracyanohepta-2,4,6-trienide By scripts.iucr.org Published On :: 2019-08-23 The title compound, C4H12N+·C11H5N4−, contains one tetramethylammonium cation and one 1,1,7,7-tetracyanohepta-2,4,6-trienide anion in the asymmetric unit. The anion is in an all-trans conjugated C=C bonds conformation. Two terminal C(CN)2 dinitrile moieties are slightly twisted from the polymethine main chain to which they are attached [C(CN)2/C5 dihedral angles = 6.1 (2) and 7.1 (1)°]. The C—C bond distances along the heptadienyl chain vary in the narrow range 1.382 (2)–1.394 (2) Å, thus indicating the significant degree of conjugation. In the crystal, the anions are linked into zigzag chains along the [10overline{1}] direction by C—H⋯N(nitrile) short contacts. The antiparallel chains stack along the [110] direction with alternating separations between the neighboring anions in stacks of 3.291 and 3.504 Å. The C—H⋯N short contacts and stacking interactions combine to link the anions into layers parallel to the (overline{1}01) plane and separated by columns of tetramethylammonium cations. Full Article text
2 Crystal structure, Hirshfeld surface analysis and computational studies of 5-[(prop-2-en-1-yl)sulfanyl]-1-[2-(trifluoromethyl)phenyl]-1H-tetrazole By scripts.iucr.org Published On :: 2019-08-23 The title compound, C11H9F3N4S, was synthesized from 2-(trifluoromethyl)aniline by a multi-step reaction. It crystallizes in the non-centrosymmetric space group Pna21, with one molecule in the asymmetric unit, and is constructed from a pair of aromatic rings [2-(trifluoromethyl)phenyl and tetrazole], which are twisted by 76.8 (1)° relative to each other because of significant steric hindrance of the trifluoromethyl group at the ortho position of the benzene ring. In the crystal, very weak C—H⋯N and C—H⋯F hydrogen bonds and aromatic π–π stacking interactions link the molecules into a three-dimensional network. To further analyse the intermolecular interactions, a Hirshfeld surface analysis, as well as interaction energy calculations, were performed. Full Article text