Di-μ-chlorido-bis­[(2,2′-bipyridine-5,5′-dicarb­oxy­lic acid-κ²N,N′)chloridocopper(II)] dimethyl­formamide tetra­solvate

In the title compound, [Cu₂Cl₄(C₁₂H₈N₂O₄)₂]·4C₃H₇NO, which contains a chloride-bridged centrosymmetric Cu^II dimer, the Cu^II atom is in a distorted square-pyramidal 4 + 1 coordination geometry defined by the N atoms of the chelating 2,2′-bipyridine ligand, a terminal chloride and two bridging chloride ligands. Of the two independent dimethyl­formamide mol­ecules, one is hydrogen bonded to a single –COOH group, while one links two adjacent –COOH groups via a strong accepted O—H...O and a weak donated C(O)—H...O hydrogen bond. Two of these last mol­ecules and the two –COOH groups form a centrosymmetric hydrogen-bonded ring in which the CH=O and the –COOH groups by disorder adopt two alternate orientations in a 0.44:0.56 ratio. These hydrogen bonds link the Cu^II complex mol­ecules and the dimethyl­formamide solvent mol­ecules into infinite chains along [-111]. Slipped π–π stacking inter­actions between two centrosymmetric pyridine rings (centroid–centroid distance = 3.63 Å) contribute to the coherence of the structure along [0-11].

Poly[bis­(1,3-dimethyl­imidazolidin-2-one)(μ₂-2,5-dioxidoterephthalato)zirconium(IV)]

In the title coordination polymer, [Zr(C₈H₂O₆)(C₅H₁₀N₂O)₂]_n, the Zr^IV atom (site symmetry 2) is coordinated by two O,O′-bidentate 2,5-dioxidoterephthalate (DHTP⁴⁻) ligands and two O-bonded 1,3-dimethyl-2-imidazolidinone (DMI) ligands (the latter in a cis orientation) in a distorted ZrO₆ octa­hedral geometry. The deprotonated hy­droxy and carb­oxy O atoms of the DHTP⁴⁻ ligand chelate the Zr^IV ion via a six-membered ring; the dihedral angle between the carboxyl­ate group and the aromatic ring is 14.46 (11)°. The DHTP⁴⁻ ligand is completed by crystallographic inversion symmetry and coordinates to two Zr^IV atoms, thereby forming polymeric zigzag chains propagating in [001].

Poly[bis­(1,3-dimethyl-1,3-diazinan-2-one)(2,5-dioxidoterephthalato)zirconium(IV)]

In the title coordination polymer, [Zr(C₈H₂O₆)(C₆H₁₂N₂O)₂]_n, the Zr^IV atom, which lies on a crystallographic twofold rotation axis, is coordinated by two O,O'-bidentate 2,5-dioxidoterephthalate (DHTP^4-) ligands and two O-bonded 1,3-dimethyl-1,3-diazinan-2-one (DMPU) ligands (the latter in a cis orientation) in a distorted ZrO₆ octa­hedral geometry. The deprotonated hy­droxy and carb­oxy O atoms of the DHTP^4- ligand chelate the Zr^IV ion via a six-membered ring; the dihedral angle between the carboxyl­ate group and the aromatic ring is 19.94 (11)°. The DHTP^4- ligand is completed by crystallographic inversion symmetry and coordinates to two Zr^IV atoms, thereby forming polymeric zigzag chains propagating in the c-axis direction.