Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 33
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Acta Crystallogr E Crystallogr Commun ; 77(Pt 3): 298-304, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33953955

RESUMO

The title compound, {[K4Ni2(C7H6N4O7)2]·4.8H2O} n , was obtained as a result of a template reaction between oxalohydrazide-hydroxamic acid, formaldehyde and nickel(II) nitrate followed by partial hydrolysis of the formed inter-mediate. The two independent [Ni(C7H6N4O7)]2- complex anions exhibit pseudo-C S symmetry and consist of an almost planar metal-containing fragment and a 1,3,5-oxadiazinane ring with a chair conformation disposed nearly perpendicularly with respect to the former. The central NiII atom has a square-planar N2O2 coordination arrangement formed by two amide N and two carboxyl-ate O atoms. In the crystal, the nickel(II) complex anions form layers parallel to the ab plane. Neighboring complex anion layers are connected by layers of potassium cations for which two of the four independent cations are disordered over two sites [ratios of 0.54 (3):0.46 (3) and 0.9643 (15):0.0357 (15)]. The framework is stabilized by an extensive system of hydrogen bonds where the water mol-ecules act as donors and the carb-oxy-lic O atoms, the amide O atoms and the oxadiazinane N atoms act as acceptors.

2.
Acta Crystallogr E Crystallogr Commun ; 76(Pt 7): 1038-1041, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32695448

RESUMO

The reaction of copper nitrate with succinic acid (succH) and N,N,N',N'-tetra-methyl-ethylenedi-amine (TMEDA) in basic solution produces the complex catena-poly[[[(N,N,N',N'-tetra-methyl-ethylenedi-amine-κ2 N,N')copper(II)]-µ-succinato-κ2 O 1:O 4] tetra-hydrate], {[Cu(C4H4O4)(C6H16N2)]·4H2O} n or {[Cu(succ)(tmeda)]·4H2O} n . Each carboxyl-ate group of the succinate ligand coordinates to a CuII atom in a monodentate fashion, giving rise to a distorted square-planar geometry. The succinate ligands bridge the CuII centres, forming one-dimensional polymeric chains. Hydrogen bonds between the ligands and water mol-ecules link these chains into sheets that lie parallel to the ac plane. Hirshfeld surface analysis, d norm and two-dimensional fingerprint plots were examined to verify the contributions of the different inter-molecular contacts within the supra-molecular structure.

3.
Acta Crystallogr E Crystallogr Commun ; 76(Pt 3): 328-331, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32148870

RESUMO

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.

4.
Acta Crystallogr E Crystallogr Commun ; 76(Pt 2): 141-144, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32071736

RESUMO

In the crystal structure of the title compound, C14H12ClNO, the mol-ecules are linked through C-H⋯O hydrogen bonds and C-H⋯π inter-actions, forming chains parallel to the [010] direction. π-π inter-actions and intra-molecular hydrogen bonds are also observed. The mol-ecular geometry of the title compound in the ground state has been calculated using density functional theory at the B3LYP level with the 6-311++G(2d,2p) basis set. Additionally, frontier mol-ecular orbital and mol-ecular electrostatic potential map analyses were performed.

5.
Acta Crystallogr E Crystallogr Commun ; 76(Pt 1): 111-114, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31921462

RESUMO

In the title compound, di-aqua-bis-(ethyl-enedi-amine-κ2 N,N')copper(II) bis-(2-nitro-benzoate), [Cu(C2H8N2)2(H2O)2](C7H4NO4)2, two di-aqua-bis-(ethyl-enedi-amine)-copper(II) cations and four nitro-benzoate anions are present in the asymmetric unit. All four anions are 'whole-mol-ecule' disordered over two sets of sites. The major components have refined occupancies of 0.572 (13), 0.591 (9), 0.601 (9) and 0.794 (10). The CuII ions exhibit slightly distorted octa-hedral geometries. In the crystal, cations and anions are connected to each other via N-H⋯O and O-H⋯O hydrogen bonds, forming a two-dimensional network parallel to (200). The inter-molecular contacts in the crystal were further analysed using Hirshfeld surface analysis, which indicates that the most significant contacts are O⋯H/H⋯O (42.9%), followed by H⋯H (35.7%), C⋯H/H⋯C (14.2%), C⋯C (2.9%), C⋯O/O⋯C (2.2%), N⋯H/H⋯N (0.9%) and N⋯O/O⋯N (0.3%).

6.
Acta Crystallogr E Crystallogr Commun ; 74(Pt 11): 1565-1568, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30443381

RESUMO

The asymmetric unit of the mononuclear mixed-ligand title complex, [Cd(C13H18NO3)2(C12H8N2)]·2H2O, contains two crystallographically independent mol-ecules that differ insignificantly in their geometrical parameters. In both, the CdII cation lies on a twofold rotation axis and is coordinated in a distorted octa-hedral fashion to two monodeprotonated residues of the l-leucine-derived ligand (S)-2-(2-hy-droxy-benzyl-amino)-4-methyl-penta-noic acid (L), as well as to a 1,10-phenanthroline ligand in a κ2 N,N' mode. The former coordinate in an N,O-chelating mode, exhibiting a trans-N,N' mutual disposition. The phenolic oxygen donor groups remain protonated and do not coordinate to the cation but take part in intra- and inter-molecular hydrogen bonds. In the crystal, O-H⋯O hydrogen bonding results in the formation of a three-dimensional network structure. The contribution to the electron density of two disordered water mol-ecules was removed with the SQUEEZE procedure in PLATON [Spek (2015 ▸). Acta Cryst. C71, 9-18]. The studied crystal was refined as a two-component inversion twin. The title complex was also characterized by IR and 1H NMR spectroscopic methods.

7.
Acta Crystallogr E Crystallogr Commun ; 74(Pt 11): 1628-1632, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30443395

RESUMO

The title compound, C13H8Br2FN3O3, is nearly planar with a dihedral angle of 10.6 (4)° between the two benzene rings. Intra-molecular N-H⋯O and O-H⋯N hydrogen bonds occur. In the crystal, the mol-ecules are linked by weak C-H⋯O and C-H⋯Br hydrogen bonds. The roles of the inter-molecular inter-actions in the crystal packing were clarified using Hirshfeld surface analysis.

8.
Acta Crystallogr E Crystallogr Commun ; 74(Pt 9): 1339-1343, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-30225129

RESUMO

In the title compound, [Cd(C16H16O3)2(C12H8N2)]·4H2O, the Cd ion lies on a twofold rotation axis and is chelated by two monodeprotonated residues of the l-tyrosine-derived ligand (S)-2-[(2-hy-droxy-benz-yl)amino]-3-(4-hy-droxy-phen-yl)propanoic acid (L) in a κ2N,O amino acid chelating mode, exhibiting an (N,N')-trans disposition, and by 1,10-phenanthroline in a κ2N,N' mode. The latter ligand is also located about the twofold rotation axis that bisects the central six-members ring. The phenolic groups remain protonated and non-coordinating and take part as acceptors in the intra-molecular hydrogen bonds with the amino groups of the acido ligands. The Cd ion is six-coordinated in a distorted octa-hedral environment. In the crystal, O-H⋯O hydrogen bonds result in the formation of three-dimensional network structures. The title complex has also been characterized by IR and 1H NMR spectroscopy and DFT studies. The crystal studied was refined as an inversion twin.

9.
Acta Crystallogr E Crystallogr Commun ; 74(Pt 7): 994-997, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30002901

RESUMO

In the title compound, C21H12N4O·H2O, the five-membered ring is essentially planar with a maximum deviation of 0.004 (2) Å. An N-H⋯O hydrogen bond connects the organic and water mol-ecules. In the crystal, O-H⋯N hydrogen bonds link mol-ecules into a two-dimensional network parallel to (100). Hirshfeld surface analyses and two-dimensional fingerprint plots were used to qu-antify the inter-molecular inter-actions present in the crystal, indicating that the most important contributions for the crystal packing are from H⋯H (28.7%), C⋯H/H⋯C (27.1%), N⋯H/H⋯N (26.4%), C⋯N/N⋯C (6.1%), O⋯H/H⋯O (3.7%) and C⋯C (6.0%) inter-actions.

10.
Acta Crystallogr E Crystallogr Commun ; 74(Pt 3): 410-413, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29765734

RESUMO

In the title Schiff base compound, C19H17N3O, the configuration about the C=N bond is E. The mol-ecule is non-planar, with the phenolic and pyridine rings being inclined to the central benzene ring by 56.59 (4) and 15.13 (14)°, respectively. In the crystal, mol-ecules are linked by pairs of O-H⋯N hydrogen bonds, forming inversion dimers. The dimers are connected to neighbouring dimers by N-H⋯O hydrogen bonds and C-H⋯π inter-actions, forming layers parallel to the bc plane. The layers are linked by offset π-π inter-actions [inter-centroid distance = 3.779 (2) Å], forming a three-dimensional supra-molecular structure. Quantum chemical calculations of the mol-ecule are in good agreement with the solid-state structure.

11.
Acta Crystallogr E Crystallogr Commun ; 71(Pt 2): m46-7, 2015 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-25878849

RESUMO

In the mononuclear title complex, [HgCl2(C22H17N3)], synthesized from the quinoline-derived Schiff base N (1)-phenyl-N (4)-[(quinolin-2-yl)methyl-idene]benzene-1,4-di-amine (PQMBD) and HgCl2, the coordination sphere around the Hg(2+) atom is distorted tetra-hedral, comprising two Cl atoms [Hg-Cl = 2.3487 (14) and 2.4490 (15) Å] and two N atom donors from the PQMBD ligand, viz. the quinolyl and the imine N atom [Hg-N = 2.270 (4) and 2.346 (4) Å, respectively]. The dihedral angle between the two benzene rings attached to the amino group is 43.7 (3)°. In the crystal, N-H⋯Cl and C-H⋯Cl hydrogen bonds, as well as π-π stacking inter-actions between one phenyl ring and the pyridine ring of the quinoline moiety of an adjacent mol-ecule [centroid-to-centroid separation = 3.617 (4) Å] are observed, resulting in a three-dimensional network.

12.
Acta Crystallogr E Crystallogr Commun ; 71(Pt 1): 28-30, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25705442

RESUMO

The title compound, C19H16N2O, crystallized with two independent mol-ecules (A and B) in the asymmetric unit. There is an intra-molecular O-H⋯N hydrogen bond in each mol-ecule with the phenol ring being inclined to the central benzene ring by 4.93 (14) and 7.12 (14)° in mol-ecules A and B, respectively. The conformation of the two mol-ecules differs essentially in the orientation of the terminal amino-phenyl ring with respect to the central benzene ring; this dihedral angle is 50.51 (4)° in mol-ecule A and 54.61 (14)° in mol-ecule B. The two outer aromatic rings are inclined to one another by 51.39 (14) and 49.88 (14)° in mol-ecules A and B, respectively. In the crystal, mol-ecules are connected by N-H⋯O hydrogen bonds generating -A-B-A-B- zigzag chains extending along [010]. The chains are linked via C-H⋯π inter-actions involving neighbouring A mol-ecules, forming slabs lying parallel to (100).

13.
Acta Crystallogr E Crystallogr Commun ; 71(Pt 1): i1-i2, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25705468

RESUMO

The title complex, poly[dodeca-µ-cyanido-diiron(III)triplat-inum(II)], [Fe(III) 2{Pt(II)(CN)4}3], has a three-dimensional polymeric structure. It is built-up from square-planar [Pt(II)(CN)4](2-) anions (point group symmetry 2/m) bridging cationic [Fe(III)Pt(II)(CN)4](+) ∞ layers extending in the bc plane. The Fe(II) atoms of the layers are located on inversion centres and exhibit an octa-hedral coordination sphere defined by six N atoms of cyanide ligands, while the Pt(II) atoms are located on twofold rotation axes and are surrounded by four C atoms of the cyanide ligands in a square-planar coordination. The geometrical preferences of the two cations for octa-hedral and square-planar coordination, respectively, lead to a corrugated organisation of the layers. The distance between neighbouring [Fe(III)Pt(II)(CN)4](+) ∞ layers corresponds to the length a/2 = 8.0070 (3) Å, and the separation between two neighbouring Pt(II) atoms of the bridging [Pt(II)(CN)4](2-) groups corresponds to the length of the c axis [7.5720 (2) Å]. The structure is porous with accessible voids of 390 Å(3) per unit cell.

14.
Acta Crystallogr E Crystallogr Commun ; 71(Pt 1): o17-8, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25705482

RESUMO

The title salt, C12H10BrN3O(2+)·2Br(-), was synthesized from the reaction of N (1),N (4)-bis-(pyridin-2-yl-methyl-idene)benzene-1,4-di-amine and bromine in a methanol solution. All non-H atoms of the 2-aza-niumyl-3-bromo-6-oxo-5,6-di-hydro-pyrido[1,2-a]quinoxalin-11-ium cation are nearly coplanar, the maximum deviation being 0.114 (4) Å. In the crystal, the cations and anions are linked through N-H⋯Br hydrogen bonds and weak C-H⋯Br inter-actions, forming a three-dimensional supra-molecular architecture. A short Br⋯Br contact [3.3088 (9) Å] is observed in the crystal.

15.
Acta Crystallogr Sect E Struct Rep Online ; 70(Pt 11): o1147-8, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25484793

RESUMO

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.

16.
Artigo em Inglês | MEDLINE | ID: mdl-24046584

RESUMO

The title compound, [Ni(C7H6N2O3)(C12H8N2)2]·3.5H2O, crystallizes as a neutral mononuclear complex with 3.5 solvent water mol-ecules. One of the water mol-ecules lies on an inversion centre, so that its H atoms are disordered over two sites. The coordination environment of Ni(II) has a slightly distorted octa-hedral geometry, which is formed by one O and five N atoms belonging to the N,O-chelating pyrazol-1-ide-5-carboxyl-ate and two N,N'-chelating phenanthroline mol-ecules. In the crystal, O-H⋯O, N-H⋯O and O-H⋯N hydrogen bonds involving the solvent water mol-ecules and pyrazole-5-carboxyl-ate ligands form layers parallel to the ab plane. These layers are linked further via weak π-π inter-actions between two adjacent phenanthroline mol-ecules, with centroid-to-centroid distances in the range 3.886 (2)-4.018 (1) Å, together with C-H⋯π contacts, forming a three-dimensional network.

17.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 6): m314-5, 2013 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-23794981

RESUMO

In the binuclear title complex, [Cu2(ClO4)1.5(NO3)1.5(C18H16N6Se)(H2O)5]NO3·H2O, both Cu(II) ions are hexa-coordinated by O and N atoms, thus forming axially elongated CuO4N2 octa-hedra. The equatorial plane of each octa-hedron is formed by one chelating pyrazole-pyridine fragment of the organic ligand and two water mol-ecules. The axial positions in one octa-hedron are occupied by a water mol-ecule and a monodentately coordinated perchlorate anion, while those in the other are occupied by a nitrate anion and a disordered perchlorate/nitrate anion with equal site occupancy. The pyrazole-pyridine units of the organic selenide are trans-oriented to each other with a C-Se-C angle of 96.01 (14)°. In the crystal, uncoordinated nitrate anions and the coordinating water mol-ecules are involved in O-H⋯O and N-H⋯O hydrogen bonds, forming a bridge between the pyrazole group and the coordinating water mol-ecules. Further O-H⋯O hydrogen bonds between the complex mol-ecules and a π-π stacking inter-action with a centroid-centroid distance of 3.834 (4) Šare also observed.

18.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 10): m1237-8, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23125573

RESUMO

In the title compound, [Co(C(10)H(8)N(2))(3)][Co(C(7)H(3)NO(4))(2)](2)(ClO(4))·0.5C(3)H(7)NO·1.3H(2)O, the Co(III) atom in the complex cation is pseudoocta-hedrally coordinated by six N atoms of three chelating bipyridine ligands. The Co(III) atom in the complex anion is coordinated by two pyridine N atoms and four carboxyl-ate O atoms of two doubly deprotonated pyridine-2,6-dicarboxyl-ate ligands in a distorted octa-hedral geometry. One dimethyl-formamide solvent mol-ecule and two water mol-ecules are half-occupied and one water mol-ecule is 0.3-occupied. O-H⋯O hydrogen bonds link the water mol-ecules, the perchlorate anions and the complex anions. π-π inter-actions between the pyridine rings of the complex anions are also observed [centroid-centroid distance = 3.804 (3) Å].

19.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 12): m1455-6, 2012 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-23468683

RESUMO

In the title compound, [Cu(C7H6N2O3)(C6H8N2)(H2O)], the Cu(II) ion is in a distorted square-pyramidal N3O2 environment formed by two bidentate chelating ligands in the equatorial coordination sites and one water mol-ecule in the apical direction. In the crystal, O-H⋯O, N-H⋯O and O-H⋯N hydrogen bonds link the complex mol-ecules into a three-dimensional supra-molecular network.

20.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 12): m1472-3, 2012 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-23468699

RESUMO

In the title binuclear complex, [Cu2(NO3)3(C18H16N6Se)(H2O)3]NO3·H2O, the Cu(II) ions are penta-coordinated in a tetra-gonal-pyramidal geometry. In both cases, the equatorial planes are formed by a chelating pyrazole-pyridine group, a water mol-ecule and a nitrate O atom, whereas the apical positions are occupied by a water mol-ecule for one Cu(II) ion and a nitrate O atom for the other. The organic selenide ligand adopts a trans configuration with respect to the C-Se-C plane. Numerous inter-molecular O-H⋯O and N-H⋯O hydrogen bonds between the coordinating and lattice water mol-ecules, nitrate anions and pyrazole groups are observed. π-π stacking inter-actions between the pyridine rings [averaged centroid-centroid distance = 3.652 (5) Å] are also present. The lattice water molecule is equally disordered over two sets of sites.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...