Crystal structure, Hirshfeld surface analysis and geometry optimization of 2-hy-droxy-imino-N-[1-(pyrazin-2-yl)ethyl-idene]propano-hydrazide.

In the mol-ecule of the title compound, C9H11N5O2, the oxime and hydrazide groups are situated in a cis-position in relation to the C-C bond linking the two functional groups. The CH3C(=NOH)C(O)NH fragment deviates from planarity because of a twist between the oxime and amide groups. In the crystal, mol-ecules are linked by O-H⋯O hydrogen bonds, forming zigzag chains in the [013] and [03] directions.

Crystal structure and Hirshfeld surface analysis of 4-{[(anthracen-9-yl)meth-yl]amino}-benzoic acid di-methyl-formamide monosolvate.

The title compound, C22H17NO2·C3H7NO, was synthesized by condensation of an aromatic aldehyde with a secondary amine and subsequent reduction. It was crystallized from a di-methyl-formamide solution as a monosolvate, C22H17NO2·C3H7NO. The aromatic mol-ecule is non-planar with a dihedral angle between the mean planes of the aniline moiety and the methyl anthracene moiety of 81.36 (8)°. The torsion angle of the Car-yl-CH2-NH-Car-yl backbone is 175.9 (2)°. The crystal structure exhibits a three-dimensional supra-molecular network, resulting from hydrogen-bonding inter-actions between the carb-oxy-lic OH group and the solvent O atom as well as between the amine functionality and the O atom of the carb-oxy-lic group and additional C-H⋯π inter-actions. Hirshfeld surface analysis was performed to qu-antify the inter-molecular inter-actions.

Crystal structure of poly[(µ3-4-amino-1,2,5-oxa-diazole-3-hydroxamato)thallium(I)].

The title compound represents the thallium(I) salt of a substituted 1,2,5-oxa-diazole, [Tl(C3H3N4O3)] n , with amino- and hydroxamate groups in the 4- and 3- positions of the oxa-diazole ring, respectively. In the crystal, the deprotonated hydroxamate group represents an inter-mediate between the keto/enol tautomers and forms a five-membered chelate ring with the thallium(I) cation. The coordination sphere of the cation is augmented to a distorted disphenoid by two monodentately binding O atoms from two adjacent anions, leading to the formation of zigzag chains extending parallel to the b axis. The cohesion within the chains is supported by π-π stacking [centroid-centroid distance = 3.746 (3) Å] and inter-molecular N-H⋯N hydrogen bonds.

Hirshfeld surface analysis and crystal structure of 7-meth-oxy-5-methyl-2-phenyl-11,12-di-hydro-5,11-methano-1,2,4-triazolo[1,5-c][1,3,5]benzoxadiazo-cine.

The title compound, C19H18N4O2, crystallizes with two independent mol-ecules in the asymmetric unit. The triazole ring is inclined to the benzene rings by 9.63 (13) and 87.37 (12)° in one mol-ecule, and by 4.46 (13) and 86.15 (11)° in the other. In the crystal, classical N-H⋯N hydrogen bonds, weak C-H⋯O hydrogen bonds and weak C-H⋯π inter-actions link the mol-ecules into a three-dimensional supra-molecular network. Hirshfeld surface analysis and two-dimensional fingerprint plots were used to investigate the inter-molecular inter-actions present in the crystal, indicating that the most important contributions for the crystal packing are from H⋯H (51.4%), H⋯C/C⋯H (26.7%), H⋯O/O⋯H (8.9%) and H⋯N/N⋯H (8%) inter-actions.

Synthesis, crystal structure and Hirshfeld surface analysis of a 1D coordination polymer catena-poly[[di-aqua-bis-(nicotinamide-κN1)nickel(II)]-µ-fumarato-κ2O1:O4].

The reaction of NiCl2 with fumaric acid and nicotinamide in basic solution produces the title polymeric complex, [Ni(C4H2O4)(C6H6N2O)2(H2O)2] n . The NiII cation, located on an inversion centre, is coordinated by two O atoms of the fumarate dianions, two N atoms from nicotinamide ligands and two water mol-ecules in a distorted octa-hedral fashion. In the crystal, the fumarate dianions bridge the NiII cations, forming polymeric chains propagating along the [101] direction; the polymeric chains are further linked by O-H⋯O, N-H⋯O and C-H⋯O hydrogen bonds, forming a three-dimensional supra-molecular architecture. Hirshfeld surface analyses and two-dimensional fingerprint plots were used to analyse the inter-molecular inter-actions present in the crystal, indicating that the most important contributions for the crystal packing are from H⋯O/O⋯H (35.9%), H⋯H (31.7%) and C⋯C (10.4%) inter-actions.

Crystal structure of 4,4'-di-nitro-[1,1'-biphen-yl]-2-amine.

In the title biphenyl derivative, C12H9N3O4, the dihedral angle between the benzene rings is 52.84 (10)°. The nitro group attached to the benzene ring is inclined to the ring by 4.03 (2)°, while the nitro group attached to the amino-substituted benzene ring is inclined to the ring by 8.84 (2)°. In the crystal, mol-ecules are linked by two pairs of N-H⋯O hydrogen bonds, forming chains propagating along [101]. Within the chains, these N-H⋯O hydrogen bonds result in the formation of R22(20) and R22(14) ring motifs. The latter ring motif is reinforced by a pair of C-H⋯O hydrogen bonds, enclosing R21(6) ring motifs. The chains are linked by a second C-H⋯O hydrogen bond, forming a three-dimensional supra-molecular structure.

Crystal structure of (E)-2,6-di-tert-butyl-4-{[2-(2,4-di-nitro-phen-yl)hydrazinylidene]meth-yl}phenol.

The essential part (including all the non-hydrogen atoms except two methyl carbons) of the mol-ecule of the title compound, C21H26N4O5, lies on a mirror plane, which bis-ects the t-butyl groups. The conformation of the C=N bond of this Schiff base compound is E, and there is an intra-molecular N-H⋯O hydrogen bond present, forming an S(6) ring motif. In the crystal, mol-ecules are linked via O-H⋯O hydrogen bonds, forming zigzag chains propagating along the a-axis direction. There are no other significant inter-molecular contacts present.

Crystal structure of (E)-2-{[(4-anilinophen-yl)imino]meth-yl}-4-nitro-phenol.

In the title compound, C19H15N3O3, which crystallizes as the phenol-imine tautomer, the dihedral angle between the aromatic rings bridged by the NH unit is 47.16 (16)°. The dihedral angle between the rings bridged by the imine unit is 6.24 (15)°; this near coplanarity is reinforced by an intra-molecular O-H⋯N hydrogen bond, which generates an S(6) ring. In the crystal, N-H⋯O hydrogen bonds generate [201] C(13) chains. The chains are reinforced and cross-linked by C-H⋯O inter-actions to generate (001) sheets.

Crystal structure of µ-oxalodi-hydroxamato-bis-[(2,2'-bipyrid-yl)(di-methyl sulfoxide-κO)copper(II)] bis-(perchlorate).

The centrosymmetric binuclear complex, [Cu2(C2H2N2O4)(C10H8N2)2(C2H6OS)2](ClO4)2, contains two copper(II) ions, connected through an N-deprotonated oxalodi-hydroxamic acid dianion, two terminal 2,2'-bi-pyridine ligands, and two apically coordinating dimethylsulfoxide mol-ecules. Two non-coordinating perchlorate anions assure electrical neutrality. The copper(II) ions in the complex dication [Cu2(C10H8N2)2(µ-C2H2N2O4)(C2H6SO)2](2+) are in an O2N3 square-pyramidal donor environment, the Cu-Cu separation being 5.2949 (4) Å. Two hydroxamate groups in the deprotonated oxalodi-hydroxamic acid are located trans to one each other. In the crystal, O-H⋯O and C-H⋯O hydrogen bonds link the complex cations to the perchlorate anions. Further C-H⋯O hydrogen bonds combine with π-π contacts with a centroid-to-centroid separation of 3.6371 (12) Što stack the mol-ecules along the a-axis direction.

Crystal structure of meso-tetra-kis-(4-nitro-phen-yl)porphyrin nitro-benzene disolvate.

The porphyrin core of the title centrosymmetric compound, C44H26N8O8·2C6H5NO2, is approximately planar, the maximum deviation being 0.069 (3) Å. The planes of the benzene rings of the nitro-phenyl substituents are almost perpendicular to the porphyrin mean plane, making dihedral angles of 73.89 (9) and 89.24 (9)°. The two pyrrole ring H atoms are equally disordered over the four pyrrole ring N atoms. In the crystal, weak C-H⋯O and C-H⋯N hydrogen bonds link the porphyrin mol-ecules into a three-dimensional supra-molecular network. The nitro-benzene solvent mol-ecules are linked by weak C-H⋯O hydrogen bonds into supra-molecular chains propagating along the a-axis direction.

Dichloridobis[3-(4-meth-oxy-phen-yl)-2-methyl-5-(piperidin-1-yl)-2,3-di-hydro-1,2,4-oxa-diazole-κN (4)]platinum(II).

In title compound, [PtCl2(C15H21N3O2)2], the Pt(II) cation, located on an inversion center, is coordinated by two Cl(-) anions and two 3-(4-meth-oxy-phen-yl)-2-methyl-5-(piperidin-1-yl)-2,3-di-hydro-1,2,4-oxa-diazole ligands in a distorted Cl2N2 square-planar geometry. The di-hydro-oxa-diazole and piperidine rings display envelope (with the non-coordinating N atom as the flap atom) and chair conformations, respectively. In the crystal, weak C-H⋯Cl hydrogen bonds link the mol-ecules into supra-molecular chains running along the b axis. The piperidine ring is disordered over two positions with the occupancy ratio of 0.528 (4):0.472 (4).

Dichloridobis[3-(4-chloro-phen-yl)-2,N,N-trimethyl-2,3-di-hydro-1,2,4-oxa-diazole-5-amine-κN (4)]platinum(II)-4-chloro-benzaldehyde (1/1).

In the title 1:1 co-crystal, [PtCl2(C11H14ClN3O)2]·C7H5ClO, the coordination polyhedron of the Pt(II) atom is slightly distorted square-planar with the chloride and 2,3-di-hydro-1,2,4-oxa-diazole ligands mutually trans, as the Pt atom lies on an inversion center. The 4-chloro-benzaldehyde mol-ecules are statistically disordered about an inversion centre with equal occupancies for the two positions. The Pt(II) complex forms a three-dimensional structure through C-H⋯Cl and weaker C-H⋯O inter-actions with the 4-chloro-benzaldehyde mol-ecule.

Poly[µ-aqua-diaquabis-[µ-2-cyano-2-(oxidoimino)-acetato]-copper(II)dipotassium].

In the title compound, [CuK(2)(C(3)N(2)O(3))(2)(H(2)O)(3)](n), the Cu(2+) atom is in a distorted square-pyramidal coordination geometry. Two N atoms belonging to the oxime groups and two O atoms belonging to the carboxyl-ate groups of two trans-disposed doubly deprotonated residues of 2-cyano-2-(hy-droxy-imino)-acetic acid make up the basal plane and the apical position is occupied by the water mol-ecule. The neighboring Cu-containing moieties are linked into a three-dimensional framework by K-O and K-N contacts formed by two potassium cations with the carboxyl-ate and the oxime O atoms and the nitrile N atoms of the ligand. The environments of the K(+) cations are complemented to octa- and nona-coordinated, by K-O contacts with H(2)O mol-ecules. The crystal structure features O-H⋯O hydrogen bonds.

Diaqua-bis-(pyridine-2-carboxyl-ato-κN,O)manganese(II) dimethyl-formamide hemisolvate.

There are two crystallographically independent complex mol-ecules with very similar geometries in the unit cell of the title compound, [Mn(C(6)H(4)NO(2))(2)(H(2)O)(2)]·0.5C(3)H(7)NO. The central ion is situated in a distorted octa-hedral environment of two N- and four O-donor atoms from two pyridine-2-carboxyl-ate ligands and two cis-disposed water mol-ecules. The carboxyl-ate ligands are coordinated in a chelate fashion with the formation of two five-membered rings. In the crystal, the complex mol-ecules are connected by O-H⋯O hydrogen bonds between the coordinated water mol-ecules and the uncoordinated carboxyl-ate O atoms, thus forming hydrogen-bonded walls disposed perpendicularly to the bc plane.

fac-Tris(pyridine-2-carboxyl-ato-κN,O)cobalt(III).

In the title compound, [Co(C(6)H(4)NO(2))(3)], the Co(III) ion lies on a threefold rotation axis and is in a distorted octa-hedral environment defined by three N and three O donor atoms from three fac-disposed pyridine-2-carboxyl-ate ligands. The ligands are coordinated in a chelate fashion, forming three five-membered rings. In the crystal, translationally related complex molecules are organized into columns along [001] via C-H⋯O hydrogen bonds.

Diaquabis-[3-(hydroxy-imino)-butanoato]nickel(II).

In the neutral, mononuclear title complex, [Ni(C(4)H(6)NO(3))(2)(H(2)O)(2)], the Ni atom lies on a crystallographic inversion centre within a distorted octa-hedral N(2)O(4) environment. Two trans-disposed anions of 3-hydroxy-imino-butanoic acid occupy four equatorial sites, coordinated by the deprotonated carboxyl-ate and protonated oxime groups and forming six-membered chelate rings, while the two axial positions are occupied by the water O atoms. The O atom of the oxime group forms an intra-molecular hydrogen bond with the coordinated carboxyl-ate O atom. The complex mol-ecules are linked into chains along b by hydrogen bonds between the water O atom and the carboxyl-ate O of a neighbouring mol-ecule. The chains are linked by further hydrogen bonds into a layer structure.

Diaquabis-[3-(hydroxy-imino-)butanoato]nickel(II): a triclinic polymorph.

The title centrosymmetric mononuclear complex, [Ni(C(4)H(6)NO(3))(2)(H(2)O)(2)], is a polymorph of the previously reported complex [Dudarenko et al. (2010 ▶). Acta Cryst. E66, m277-m278]. The Ni(II) atom, lying on an inversion center, is six-coordinated by two carboxyl-ate O atoms and two oxime N atoms from two trans-disposed chelating 3-hydroxy-imino-butanoate ligands and two axial water mol-ecules in a distorted octa-hedral geometry. The hydr-oxy group forms an intra-molecular hydrogen bond with the coordinated carboxyl-ate O atom. The complex mol-ecules are linked in stacks along [010] by a hydrogen bond between the water O atom and the carboxyl-ate O atom of a neighboring mol-ecule. The stacks are further linked by O-H⋯O hydrogen bonds into a layer parallel to (001).

µ-Peroxido-bis-[acetonitrile-bis-(ethyl-enediamine)-cobalt(III)] tetrakis(per-chlorate).

The title compound, [Co(2)(O(2))(CH(3)CN)(2)(C(2)H(8)N(2))(4)](ClO(4))(4), consists of centrosymmetric binuclear cations and perchlorate anions. Two Co(III) atoms, which have a slightly distorted octa-hedral coordination, are connected through a peroxido bridge; the O-O distance is 1.476 (3) Å. Both acetonitrile ligands are situated in a trans position with respect to the O-O bridge. In the crystal, the complex cations are connected by N-H⋯O hydrogen bonds between ethyl-endiamine NH groups and O atoms from the perchlorate anions and peroxide O atoms.

Poly[bis-[µ(4)-N-(2-hydroxy-imino-propion-yl)-N'-(2-oxidoimino-propion-yl)propane-1,3-diaminato]dimethano-lcalciumdicopper(II)].

In the title compound, [CaCu(2)(C(9)H(13)N(4)O(4))(2)(CH(3)OH)(2)](n), the Ca(II) atom lies on an inversion center and is situated in a moderately distorted octa-hedral environment. The Cu(II) atom is in a distorted square-pyramidal geometry, defined by four N atoms belonging to the amide and oxime groups of the triply deprotonated residue of N,N'-bis-(2-hydroxy-imino-propano-yl)propane-1,3-diamine (H(4)pap) and one oxime O atom from a neighboring Hpap ligand at the apical site, forming a dimeric [Cu(2)(Hpap)(2)](2-) unit. Each dimeric unit connects four Ca atoms and each Ca atom links four [Cu(2)(Hpap)(2)](2-) units through Ca-O(amide) bonds, leading to a three-dimensional framework. The crystal structure involves intra- and inter-molecular O-H⋯O hydrogen bonds.

N-(2-Hydroxy-ethyl)-2-[2-(hydroxy-imino)propanamido]ethanaminium 2-(hydroxy-imino)propanoate.

The cation of the title salt, C(7)H(16)N(3)O(3) (+)·C(3)H(4)NO(3) (-), the oxime group is trans with respect to the amide-carbonyl group. The components of the structure are united into a three-dimensional network by an extensive system of O-H⋯O and N-H⋯O hydrogen bonds.