Poly[[tris-(µ(2)-4,4'-bipyridine N,N'-di-oxide)hexa-nitratodieuropium(III)] dichloro-methane disolvate].

The title one-dimensional coordination network, {[Eu(2)(NO(3))(6)(C(10)H(8)N(2)O(2))(3)]·2CH(2)Cl(2)}(n), is isostructural with the previously reported Tb and Tl coordination networks and to its Gd analog. The Eu(III) cation is coordinated in a distorted tricapped trigonal-prismatic fashion by nine O atoms from three bridging 4,4'-bipyridine N,N'-dioxide ligands and three chelating nitrate anions. None of the atoms lie on a special position, but there is an inversion center located between the rings of one of the ligands. The network topology is ladder-like, and each ladder inter-acts with six neighboring ladders through C-H⋯O hydrogen bonds. The packing motif of the ladders allows for the formation of channels that run parallel to the a axis; these channels are filled with CH(2)Cl(2) solvent mol-ecules that inter-act with the ladders through C-H⋯O hydrogen bonds.

Poly[[tris-(µ(2)-4,4'-bipyridine N,N'-di-oxide)hexa-nitratodigadolinium(III)] dichloro-methane disolvate].

The title one-dimensional coordination network, {[Gd(2)(NO(3))(6)(C(10)H(8)N(2)O(2))(3)]·2CH(2)Cl(2)}(n), is isostructural with the previously reported Tb and Tl coordination networks and to its Eu analog. The Gd(III) cation is coordinated in a distorted tricapped trigonal-prismatic fashion by nine O atoms from three bridging 4,4'-bipyridine N,N'-dioxide ligands and three chelating nitrate anions. None of the atoms lie on a special position, but there is an inversion center located between the rings of one of the ligands. The network topology is ladder-like, and each ladder inter-acts with six neighboring ladders through C-H⋯O hydrogen bonds. The packing motif of the ladders allows for the formation of channels that run parallel to the a axis; these channels are filled with CH(2)Cl(2) solvent mol-ecules that inter-act with the ladders through C-H⋯O hydrogen bonds.

Poly[[tetra-kis-(µ(2)-pyrazine N,N'-dioxide-κO:O')neodymium(III)] tris-(perchlorate)].

The title three-dimensional coordination network, {[Nd(C(4)H(4)N(2)O(2))(4)](ClO(4))(3)}(n), is isostructural to that of other lanthanides. The Nd(+3 )cation lies on a fourfold roto-inversion axis. It is coordinated in a distorted square-anti-prismatic fashion by eight O atoms from bridging pyrazine N,N'-dioxide ligands. There are two unique pyrazine N,N'-dioxide ligands. One ring is located around an inversion center, and there is a twofold rotation axis at the center of the other ring. There are also two unique perchlorate anions. One is centered on a twofold rotation axis and the other on a fourfold roto-inversion axis. The perchlorate anions are located in channels that run perpendicular to (001) and (110) and inter-act with the coordination network through C-H⋯O hydrogen bonds.

Poly[[tetra-kis-(µ(2)-pyrazine N,N'-dioxide-κO:O')dysprosium(III)] tris-(perchlorate)].

The title three-dimensional coordination network, {[Dy(C(4)H(4)N(2)O(2))(4)](ClO(4))(3)}(n), is isostructural of other lanthanides. The Dy(+3 )cation lies on a fourfold roto-inversion axis. It is coordinated in a distorted square-anti-prismatic fashion by eight O atoms from bridging pyrazine N,N'-dioxide ligands. There are two unique pyrazine N,N'-dioxide ligands. One ring is located around an inversion center, and there is a a twofold rotation axis at the center of the other ring. There are also two unique perchlorate anions. One is centered on a twofold rotation axis and the other on a fourfold roto-inversion axis. The perchlorate anions are located in channels that run perpendicular to (001) and (110) and inter-act with the coordination network through C-H⋯O hydrogen bonds.

Poly[[tetra-kis-(µ(2)-pyrazine N,N'-dioxide-κO:O')holmium(III)] tris-(perchlorate)].

The title three-dimensional coordination network, {[Ho(C(4)H(4)N(2)O(2))(4)](ClO(4))(3)}(n), is isostructural to that of other lanthanides. The Ho(+3 )cation lies on a fourfold roto-inversion axis. It is coordinated in a distorted square anti-prismatic fashion by eight O atoms from bridging pyrazine N,N'-dioxide ligands. There are two unique pyrazine N,N'-dioxide ligands. One ring is located around an inversion center, and there is a a twofold rotation axis at the center of the other ring. There are also two unique perchlorate anions. One is centered on a twofold rotation axis and the other on a fourfold roto-inversion axis. The perchlorate anions are located in channels that run perpendicular to (001) (110) and inter-act with the coordination network through C-H⋯O hydrogen bonds.

Poly[[tetra-kis-(µ(2)-pyrazine N,N'-dioxide-κO:O')erbium(III)] tris-(perchlorate)].

The title three-dimensional coordination network, {[Er(C(4)H(4)N(2)O(2))(4)](ClO(4))(3)}(n), is isostructural to that of other lanthanides. The Er(+3 )cation lies on a fourfold roto-inversion axis. It is coordinated in a distorted square-anti-prismatic fashion by eight O atoms from bridging pyrazine N,N'-dioxide ligands. There are two unique pyrazine N,N'-dioxide ligands. One ring is located around an inversion center, and there is a a twofold rotation axis at the center of the other ring. There are also two unique perchlorate anions. One is centered on a twofold rotation axis and the other on a fourfold roto-inversion axis. The perchlorate anions are located in channels that run perpendicular to (001) and (110) and inter-act with the coordination network through C-H⋯O hydrogen bonds.

1,2-Di-4-pyridylethane N,N'-dioxide-acetic acid (1/2).

The title compound, C(12)H(12)N(2)O(2)·2C(2)H(4)O(2), was prepared from 1,2-di-4-pyridylethane, acetic acid, and hydrogen peroxide. The 1,2-di-4-pyridylethane N,N'-dioxide mol-ecule is located on an inversion center. π-π stacking inter-actions between neighboring 1,2-di-4-pyridylethane N,N'-dioxide mol-ecules are observed with a centroid-centroid distance of 3.613 Å, an inter-planar distance of 3.317 Å, and a slippage of 1.433 Å. O-H⋯O hydrogen-bonding inter-actions between 1,2-di-4-pyridylethane N,N'-dioxide and acetic acid mol-ecules result in distinct hydrogen-bonded units made of one N-oxide and two acetic acid mol-ecules. These units are then linked into a three-dimensional network through weaker C-H⋯O hydrogen-bonding inter-actions.

2-Methyl-pyrazine 1,4-dioxide.

The title compound, C(5)H(6)N(2)O(2), was prepared from 2-methyl-pyrazine, acetic acid and hydrogen peroxide. In the crystal, π-π stacking inter-actions between neighboring mol-ecules are observed, with a centroid-centroid distance of 3.7370 Å, an inter-planar distance of 3.167 Å, and a slippage of 1.984 Å. Each mol-ecule is linked to four neighbors through C-H⋯O hydrogen-bonding inter-actions, forming one-dimensional ribbons.

2,5-Dimethyl-pyrazine 1,4-dioxide.

The title compound, C(6)H(8)N(2)O(2), was prepared from 2,5-dimethyl-pyrazine, acetic acid, and hydrogen peroxide. The 2,5-dimethyl-pyrazine 1,4-dioxide mol-ecule is located on an inversion center. π-π inter-actions between neighboring 2,5-dimethyl-pyrazine 1,4-dioxide mol-ecules are observed with an inter-planar distance of 3.191 Å. Each 2,5-dimethyl-pyrazine 1,4-dioxide mol-ecule is linked to four neighboring N-oxide mol-ecules through C-H⋯O hydrogen-bonding inter-actions, forming two-dimensional layers.

Bis{bis-(azido-κN)bis-[bis-(pyridin-2-yl-κN)amine]cobalt(III)} sulfate dihydrate.

The search for new mol-ecular materials with inter-esting magnetic properties, using the pseudohalide azide ion and di-2-pyridyl-amine (dpa, C10H9N3) as a chelating ligand, led to the synthesis and structure determination of the title compound, [Co(N3)2(dpa)2]2SO4·2H2O. The crystal structure comprises discrete [Co(dpa)2(N3)2](+) cations, sulfate anions, as well as H2O solvent mol-ecules. The Co(III) cations display a slightly distorted octa-hedral coordination sphere defined by two N atoms from azide anions and four N atoms from the pyridyl rings of two dpa ligands. In the crystal, extensive C-H⋯O, N-H⋯O, and O-H⋯O inter-actions result in supra-molecular sheets that lie parallel to the ab plane. The sheets are further linked through O-H⋯N inter-actions between the water mol-ecules of one sheet and azide anions of another sheet, forming a supra-molecular framework.

Crystal structures of [Ln(NO3)3(µ2-bpydo)2], where Ln = Ce, Pr or Nd, and bpydo = 4,4'-bi-pyridine N,N'-dioxide: layered coordination networks containing 4(4) grids.

Three isostructural coordination networks of Ce, Pr, and Nd nitrate with 4,4'-bi-pyridine N,N'-dioxide (bpydo) are reported, namely poly[[tris-(nitrato-κ(2) O,O')cerium(III)]-bis-(µ2-4,4'-bi-pyridine N,N'-dioxide-κ(2) N:N')], [Ce(NO3)3(C10H8N2O2)2], poly[[tris-(nitrato-κ(2) O,O')praeseodymium(III)]-bis-(µ2-4,4'-bi-pyridine N,N'-dioxide-κ(2) N:N')], [Pr(NO3)3(C10H8N2O2)2], and poly[[tris(nitrato-κ(2) O,O')neodymium(III)]-bis-(µ2-4,4'-bi-pyridine N,N'-dioxide-κ(2) N:N'], [Nd(NO3)3(C10H8N2O2)2]. All three compounds are isostructural to the previously reported La analogue. The asymmetric unit of [Ln(NO3)3(µ2-bpydo)2] contains one lanthanide cation, two bpydo ligands, and three nitrate anions. Both bpydo ligands act as end-to-end µ2-bridges and display nearly ideal cis and gauche conformations, respectively. The bpydo ligands link the ten-coordinate Ln (III) cations, forming inter-digitating 4(4) grid-like layers extending parallel to (-101), where inter-digitation of layers is promoted by C-H⋯O inter-actions between nitrate anions and bpydo ligands. The inter-digitated layers are linked to sets of neighboring layers via further C-H⋯O and π-π inter-actions.

Crystal structure of di-µ-aqua-µ-(pyrazine N,N'-dioxide)-κ(2) O:O-bis-(di-aqua-sodium) tetra-phenyl-borate dihydrate pyrazine N,N'-dioxide monosolvate.

The search for novel lanthanide coordination networks using pyrazine N,N'-dioxide (pzdo, C4H4N2O2) as a structure-directing unit, led to the synthesis and the structure determination of the title compound, [Na2(C4H4N2O2)(H2O)6][B(C6H5)4]2·C4H4N2O2·2H2O. The crystal structure is comprised of discrete [{Na(H2O)2}2(µ-H2O)2(µ-pzdo)](2+) cations and tetra-phenyl-borate anions, as well as pzdo and H2O solvent mol-ecules. The dinuclear cation is located about a twofold rotation axis, and the symmetry-related Na(I) atoms display a distorted square-pyramidal coordination sphere defined by two O atoms of terminal water ligands, two O atoms of bridging water ligands and one O atom of a bridging pzdo ligand. In the crystal, O-H⋯O hydrogen bonds link the dinuclear cation and solvent pzdo mol-ecules (point-group symmetry -1) into rectangular grid-like layers parallel to the bc plane. Additional C-H⋯O, O-H⋯O, C-H⋯π and O-H⋯π inter-actions link the anion and solvent water mol-ecules to the layers. The layers are further linked into a three-dimensional network through a combination of C-H⋯π and O-H⋯π hydrogen bonds involving the tetra-phenyl-borate anion.

A host-guest complex between a metal-organic cyclotriveratrylene analog and a polyoxometalate: [Cu6(4,7-phenanthroline)8(MeCN)4]2PM12O40(M = Mo or W).

The synthesis and crystal structure of Cu(6)(4,7-phenanthroline)(8)(MeCN)(4)(6+) a novel Cu(i)-molecular hexamer is described in which the metal cations and phenanthroline molecules self-assemble into a dimer of shallow triangular-shaped bowls, within which are located large spherical polyoxometalate anions PM(12)O(40)(3-)(M = Mo or W).

A polyoxometallate-templated coordination polymer: synthesis and crystal structure of [Cu3(4,4'-bipy)5(MeCN)2]PW12O(40).2C6H5CN.

The spherical phosphotungstate ion, PW12O40(3-), has been used as a non-coordinating anionic template for the construction of a novel, three-dimensional Cu(I) coordination polymer.

A mixed-ligand coordination polymer from the in situ, Cu(I)-mediated isomerization of bis(4-pyridyl)ethylene.

Reaction of [Cu(PPh(3))(2)(MeCN)(2)]PF(6) and trans-1,2-bis(4-pyridyl)ethylene (bpe) results in the trans-cis isomerization of the bpe and subsequent formation of a mixed-isomer linear coordination polymer over the course of several days or weeks depending on solvent. The one unique copper atom in the structure is coordinated to two bridging cis-bpe ligands, one bridging trans-bpe ligand, and one terminal triphenylphoshine ligand to create [Cu(trans-bpe)(0.5)(cis-bpe)(PPh(3))](+)( infinity ) zigzag chains. The reaction requires both visible light and Cu(I), and the crystallization of this particular coordination polymer is insensitive to the ratio of trans:cis isomers in solution, occurring both from trans-rich and cis-rich solutions.