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1.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 11): m586-7, 2013 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-24454025

RESUMO

In the title compound, {[Pr(C14H8O5)(C14H9O5)(H2O)2]·H2O} n , the Pr(III) cation is eight-coordinated by six carboxyl O atoms from both a monoanionic 4-(4-carb-oxy-phen-oxy)benzoate and a dianionic 4,4'-oxydibenzoate ligand (four bridging with two from a bidentate chelate inter-action), and two O-atom donors from water mol-ecules. A single water mol-ecule of solvation is also present. The complex units are linked through carboxyl O:O' bridges giving a two-dimensional sheet polymer lying parallel to (001). An overall three-dimensional network structure is generated through inter-molecular carb-oxy-lic acid and water O-H⋯O hydrogen bonds and weak C-H⋯O inter-actions.

2.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 11): o1613, 2013 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-24454064

RESUMO

The mol-ecule of the title compound, C22H12N4O2, is located on a twofold rotation axis. The dihedral angle between the furan and pyrazine rings is 34.8 (7)°, and that between the furan rings is 46.92 (7)°. A π-π stacking interaction occurs between adjacent pyrazino[2,3-f][1,10]phenanthroline units, with an interplanar distance of 3.5862 (12) Å.

3.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 4): m368, 2012 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-22589763

RESUMO

In the title compound, [Co(C(8)Cl(4)O(4))(C(3)H(4)N(2))(2)(H(2)O)(2)](n), the Co(II) ion displays a distorted octa-hedral coordination geometry with two O atoms from two monodentate tetra-chloro-terephthalate dianions, two N atoms from two imidazole mol-ecules and two O atoms from two water mol-ecules. The Co(II) ions are connected via the tetra-chloro-terephthalate dianions into a chain running along the crystallographic [110] direction. Adjacent chains are linked into a two-dimensional network arranged parallel to (010) by classical N-H⋯O and O-H⋯O hydrogen bonds.

4.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 5): o1443, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-22590322

RESUMO

The mol-ecule of the title compound, C(22)H(12)N(4)S(2), shows no crystallographic symmetry. The thiophene rings form different dihedral angles [40.15 (9) and 15.43 (10)°] with the pyrazine ring. A strong π-π stacking inter-action occurs between adjacent pyrazine-[2,3-f][1,10]phenanthroline units with an inter-planar distance of 3.4352 (16) Å.

5.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 12): o3144, 2011 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-22199671

RESUMO

In the mol-ecule of title compound, C(16)H(24)N(2)Si(2), the pyridine rings are nearly planar (r.m.s. deviation = 0.002 Å).

6.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 12): m1618, 2010 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-21589294

RESUMO

The asymmetric unit of the title compound, {[Ni(C(8)Cl(4)O(4))(C(5)H(5)N)(3)(H(2)O)]·C(5)H(5)N}(n), contains two independent nickel(II) cations displaying a distorted octa-hedral coordination geometry provided by the N atoms of three pyridine mol-ecules, the O atom of a water mol-ecule, and O atoms of two monodentate µ(2)-bridging tetra-chloro-terephthalate dianions. The metal atoms are linked by the dianions into zigzag chains running parallel to [11]. The crystal packing is stabilized by O-H⋯N and O-H⋯O hydrogen bonds.

7.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 7): m879, 2008 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-21202750

RESUMO

In the title compound, [Ni(C(8)F(4)O(4))(C(5)H(5)N)(2)(CH(4)O)(2)](n), the Ni(II) ion is located on an inversion center and is coordinated by four O atoms [Ni-O = 2.079 (4) Å] from two tetra-fluoro-terephthalate ligands and two methanol mol-ecules, and by two N atoms [Ni-N = 2.127 (4) Å] from two pyridine ligands in a distorted octa-hedral geometry. The Ni(II) ions are connected via the tetra-fluoro-terephthalate anions into a one-dimensional chain running along the crystallographic [011] direction.

8.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 7): m965, 2008 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-21202811

RESUMO

In the title compound, [Cu(C(8)F(4)O(4))(C(5)H(5)N)(3)](n), the Cu(II) atom, lying on a twofold rotation axis, is five-coordinated by two O atoms from two tetra-fluoro-terephthalate ligands and three N atoms from three pyridine ligands in a distorted trigonal-bipyramidal geometry. Adjacent Cu(II) atoms are connected via the bridging tetra-fluoro-terephthalate ligands into a one-dimensional chain running along the [101] direction.

9.
Acta Crystallogr E Crystallogr Commun ; 71(Pt 5): m124-5, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25995896

RESUMO

In the title compound, [Pd(C6H4F)I(C6H16N2)], the Pd(II) atom is coordinated by two N atoms from the N,N,N',N'-tetra-methyl-ethylenedi-amine ligand, a C atom of the 4-fluoro-phenyl group and an iodide ligand in a distorted square-planar geometry, with an average deviation from the least-squares plane through the ligand donor atoms of 0.0159 (2) Å. The angles about the Pd(II) atom range from 83.35 (16) to 178.59 (11)°. In the crystal, weak C-H⋯F and C-H⋯I hydrogen bonds link the mol-ecules into sheets in the bc plane.

10.
Carbohydr Polym ; 90(2): 792-8, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-22840003

RESUMO

Efficient catalytic conversion of microcrystalline cellulose (MCC) to 5-hydroxymethyl furfural (HMF), is achieved using acidic ionic liquids (ILs) as the catalysts and metal salts as co-catalysts in the solvent of 1-ethyl-3-methylimidazo-lium acetate ([emim][Ac]). A series of acidic ILs has been synthesized and tested in conversion of MCC to HMF. The effect of reaction conditions, such as reaction time, temperature, catalyst dosage, metal salts, water dosage, Cu(2+) concentration and various acidic ILs are investigated in detail. The results show that CuCl(2) in 1-(4-sulfonic acid) butyl-3-methylimidazolium methyl sulfate ([C(4)SO(3)Hmim][CH(3)SO(3)]), is found to be an efficient catalyst for catalytic conversion of MCC to HMF, and 69.7% yield of HMF is obtained. A mechanism to explain the high activity of CuCl(2) in [C(4)SO(3)Hmim][CH(3)SO(3)] is proposed. To the best of our knowledge, this report first proposes that the Cu(2+) and [C(4)SO(3)Hmim][CH(3)SO(3)] show better catalytic performance in catalytic conversion of MCC to HMF.


Assuntos
Ácidos/farmacologia , Celulose/metabolismo , Furaldeído/análogos & derivados , Líquidos Iônicos/farmacologia , Catálise , Celulose/química , Estabilidade de Medicamentos , Eficiência , Furaldeído/química , Furaldeído/farmacocinética , Modelos Biológicos , Concentração Osmolar , Solventes/farmacologia , Temperatura , Fatores de Tempo
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