trans‐Bis(benzoato‐O)tetrakis(methanol‐O)iron(II): ligand bulk is not structure‐determining

The title compound, [Fe(C₇H₅O₂)₂(CH₄O)₄], is a centrosymmetric six‐coordinate Fe^II complex coordinated by two axial monodentate benzoate ligands and four methanol ligands in the equatorial plane [Fe—O_benzoate 2.0935 (7) Å, and Fe—O_methanol 2.1310 (7) and 2.1290 (7) Å]. The benzoate ligands adopt monodentate ligation, rather than a bridged polymeric structure, because of strong intra‐ and intermolecular hydrogen bonds to the methanol ligands. This structure is nearly identical to that obtained with a much bulkier carboxyl­ate ligand [Chavez, Que & Tolman (2001). Chem. Commun. pp. 111–112].     

Dichlorobis(dl‐proline‐κO)zinc(II)

The title compound, [ZnCl₂(C₅H₉NO₂)₂], crystallizes in the centrosymmetric space group C2/c with the Zn atom on a twofold axis. The two proline residues in any one complex thus have the same absolute configuration. Hydrogen bonding links the mol­ecules into linear chains, which run in the crystallographic b direction. The proline residues within any one chain also have an identical absolute configuration.     

Bis(dimethyl sulfoxide‐S)tetrakis(μ‐p‐hydroxybenzoato‐O:O′)dirhodium(II)–tetrakis(μ‐butyrato‐O:O′)bis(dimethyl sulfoxide‐S)dirhodium(II) cocrystal ethanol disolvate

The title structure, [Rh₂(C₇H₅O₃)₄(C₂H₆OS)₂]·[Rh₂(C₄H₇­O₂)₄(C₂H₆OS)₂]·2C₂H₆O, contains two discrete neutral Rh–Rh dimers cocrystallized as the ethanol disolvate. Each dimer is situated on an inversion center. The butyrate chain displays disorder in one C‐atom position. In each dimer, the di­methyl sulfoxide ligand (dmso) is bound via S, as expected. The ethanol is a hydrogen‐bond acceptor for one p‐hydroxy­benzoate hydroxyl group and acts as a hydrogen‐bond donor to the dmso O atom of a neighboring p‐hydroxy­benzoate dirhodium complex. A third hydrogen bond is formed from the other p‐hydroxy­benzoate hydroxyl group to the dmso O atom of a butyrate–dirhodium complex.     

cis‐Di­aqua­bis(trans‐cinnamato‐O,O′)zinc(II)

The title complex, [Zn(C₉H₇O₂)₂(H₂O)₂], shows a distorted octahedral coordination and has a crystallographic twofold rotation axis. Intermolecular O—H?O hydrogen bonding forms a two‐dimensional network in the ab plane.     

Polymeric bis(N,N‐dimethylacetamide)tetrakis(thiocyanato)cadmium(II)mercury(II)

The title complex, {[CdHg(SCN)₄(C₄H₉NO)₂]₂}_n, contains two crystallographically independent Cd^II centres and two Hg^II centres. Each Cd^II atom is bound to four N atoms belonging to SCN groups and to two O atoms from N,N‐di­methyl­acet­amide (DMA) ligands in an octahedral geometry. Each Hg^II centre is tetrahedrally coordinated by four SCN S atoms.     

Aqua(benzene‐1,3‐dicarboxylato)zinc(II)

The title compound, poly­[[aqua­zinc(II)]‐μ‐benzene‐1,3‐di­carboxyl­ato‐O¹:O^1′:O²], [Zn(C₈H₄O₄)(H₂O)]_n, forms a metal–organic coordination network that consists of tetrahedral Zn atoms bonded to one water mol­ecule and three carboxyl­ate groups. Isophthalate groups bridge the four‐coordinate Zn centers to generate two‐dimensional architectures in the ac plane. These planar zinc isophthalate motifs are linked by infinite C=O?H—O—H interactions along the a axis to form a chiral framework. The observed polar structural pattern originates due to the distorted tetrahedral Zn centers [O—Zn—O 100.7 (2)–136.0 (1)°] and the alignment of the water mol­ecules. Bridging isophthalate groups align to form approximate centrosymmetric motifs.     

Dichlorobis(2‐methylquinoline N‐oxide‐κO)zinc(II) from powder data

The crystal structure of the title compound, [ZnCl₂(C₁₀H₉NO)₂], has been determined from laboratory powder diffraction data. Although the powder pattern was initially indexed with tetragonal unit‐cell dimensions, the correct solution was found in an orthorhombic space group using a combination of grid‐search and simulated‐annealing techniques. The subsequent bond‐restrained Rietveld refinement gave bond lengths and angles within expected ranges. The molecule has crystallographically imposed twofold symmetry.     

trans‐Di­chloro­tetrakis(4‐methylpyrimidine‐N1)­ruthenium(II)

The title compound, trans‐[Ru^IICl₂(N¹‐mepym)₄] (mepym is 4‐methylpyrimidine, C₅H₆N₂), obtained from the reaction of trans,cis,cis‐[Ru^IICl₂(N¹‐mepym)₂(SbPh₃)₂] (Ph is phenyl) with excess mepym in ethanol, has fourfold crystallographic symmetry and has the four pyrimidine bases coordinated through N¹ and arranged in a propeller‐like orientation. The Ru—N and Ru—Cl bond distances are 2.082 (2) and 2.400 (4) Å, respectively. The methyl group, and the N³ and Cl atoms are involved in intermolecular C—H?N and C—­H?Cl hydrogen‐bond interactions.     

trans‐Tetra­aqua­bis(5‐fluorouracil‐1‐acetato‐O)­zinc(II) tetrahydrate

In the title complex, [Zn(C₆H₄FN₂O₄)₂(H₂O)₄]·4H₂O, the Zn atom is located at a center of symmetry and has a distorted octahedral geometry, with Zn—O distances in the range 2.052 (2)–2.181 (2) Å. Hydro­gen bonds involving the water mol­ecules make up a three‐dimensional network.     

Diamminebis(2,4,6‐tribromophenolato‐O)copper(II)

The title compound, [Cu(C₆H₂Br₃O)₂(NH₃)₂], a monomeric centrosymmetric Cu^II complex, crystallizes in the monoclinic system. The CuO₂N₂ coordination sphere is trans planar, [Cu—O 1.943 (5) Å and Cu—N 1.977 (6) Å], with the fifth and sixth coordination sites occupied by Br atoms from the phenoxide ions [Cu—Br 3.129 (1) Å], resulting in an elongated distorted octahedral structure for the CuO₂N₂Br₂ coordination. Each of the NH₃ groups forms two hydrogen bonds with the Br and O atoms of the CuO₂N₂Br₂ moiety of a neighbouring mol­ecule. This arrangement constitutes a one‐dimensional chain along the x axis of the unit cell.     

Tetraaquabis(3,5‐dicarboxybenzoato‐O)cobalt(II)

The hydro­thermal reaction of cobalt(II) chloride with trimesate (3,5‐di­carboxy­benzoate) ions in aqueous solution gives the novel title complex, [Co(C₉H₅O₆)₂(H₂O)₄]. The Co^II ion lies on an inversion centre and is octahedrally coordinated to two trimesate anions and four water mol­ecules. Hydro­gen bonds ensure the three‐dimensional architecture of the structure.     

Di­chloro­tetrakis(3‐phenyl­pyrazole‐κN2)copper(II)

In the title compound, [CuCl₂(C₉H₈N₂)₄], there are two independent mol­ecules in the asymmetric unit. The Cu²⁺ ions lie on inversion centres and are octahedrally coordinated by two Cl atoms and four pyrazole N atoms. All pyrazole N—H groups form intramolecular hydrogen bonds, giving rise to five‐membered hydrogen‐bonded rings incorporating the Cu atoms.     

Tetrakis(dimethyl sulfide)palladium(II) bis(tetrafluoroborate) and tetrakis(1,4‐oxathiane‐κS)palladium(II) bis(tetrafluoroborate)

Tetrakis(dimethyl sulfide)palladium(II) bis(tetrafluoroborate), [Pd(C₂H₆S)₄](BF₄)₂, (I), and tetrakis(1,4‐oxa­thiane‐κS)palladium(II) bis­(tetra­fluoro­borate), [Pd(C₄H₈OS)₄](BF₄)₂, (II), both crystallize as mononuclear square‐planar complexes with tetra­fluoro­borate as the counter‐ions. The Pd atom accepts four S‐donor atoms and is positioned at an inversion centre in both compounds. The two unique S atoms in the di­methyl sulfide complex, (I), are disordered. The Pd—S distances are in the range 2.3338 (12)–2.3375 (12) Å in (I), and the corresponding distances in the thio­xane complex, (II), are 2.3293 (17) and 2.3406 (17) Å. The anions in both compounds interact weakly with the Pd atom.     

Bis(thiosemicarbazide‐S,N)zinc(II) dinitrate

In the title compound, [Zn(CH₅N₃S)₂](NO₃)₂, the zinc(II) ion is located on the twofold axis and chelated by two thiosemicarbazide ligands with Zn—S and Zn—N distances of 2.0904 (17) and 2.2672 (6) Å, respectively. Thus the central zinc(II) is four‐coordinated and in a distorted tetrahedral geometry. The inter‐ and intramolecular hydrogen bonds formed between thiosemicarbazide ligands and nitrate anions assemble the molecules into a one‐dimensional chain.     

Copper(II) and zinc(II) complexes of pyridine‐2,6‐di­carboxyl­ic acid

The title compounds, bis­(pyridine‐2,6‐di­carboxyl­ato‐N,O,O′)copper(II) monohydrate, [Cu(C₇H₄NO₄)₂]·H₂O, andbis(pyridine‐2,6‐dicarboxylato‐N,O,O′)zinc(II) trihydrate, [Zn(C₇H₄NO₄)₂]·3H₂O, have distorted octahedral geometries about the metal centres. Both metal ions are bonded to four O atoms and two pyridyl‐N atoms from the two terdentate ligand mol­ecules, which are nearly perpendicular to each other. The copper(II) complex has twofold crystallographic symmetry and contains two different ligand mol­ecules, one of which is neutral and another doubly ionized. In contrast, the zinc(II) complex contains two identical singly ionized ligand mol­ecules. Both crystal structures are stabilized by O—H?O intermolecular hydrogen bonds between the complex and the water mol­ecules.     

trans‐Di­aqua­tetrakis(3,5‐di­methyl­pyrazole‐N2)­nickel(II) dichloride

The X‐ray structure analysis of [Ni(C₅H₈N₂)₄(H₂O)₂]Cl₂ was undertaken to elucidate the geometry around the Ni²⁺ ion. The molecule lies on a twofold axis which runs through the O—Ni—O atoms. The geometry around the Ni²⁺ ion is best described as slightly distorted tetragonal bipyramidal.     

Poly[tetraaquadi‐μ4‐malonato‐barium(II)zinc(II)]

The title complex, [BaZn(C₃H₂O₄)₂(H₂O)₄]_n, is polymeric, due to the connectivity brought about by each malonate dianion bonding to two different Zn^II cations and two different Ba^II cations. The Ba^II cations, on crystallographic twofold axes, have slightly distorted square‐anti­prismic coordination, with Ba—O distances ranging from 2.795 (2) to 2.848 (2) Å. The Zn^II cations, which lie on crystallographic centres of symmetry, have distorted octa­hedral coordination, with Zn—O bonds in the range 2.0364 (19)–2.3248 (18) Å. The water mol­ecules participate in extensive O—H⋯O hydrogen bonding. The structure comprises alternating layers along [100], with one type containing Zn^II cations and malonate dianions, while the other is primarily composed of Ba^II cations and water mol­ecules.     

Diaqua­malonato(1,10‐phenanthro­line)­zinc(II)

In the crystal structure of the title complex, [Zn(C₃H₂O₄)(C₁₂H₈N₂)(H₂O)₂], the Zn^II atom displays a distorted octa­hedral geometry, being coordinated by two N atoms from the 1,10‐phenanthroline ligand, two O atoms from different carboxyl­ate groups of the chelating malonate dianion and two O atoms of cis water mol­ecules. The complex mol­ecules are linked to form a three‐dimensional supramolecular array by both hydrogen‐bonding inter­actions between coordinated water molecules and the uncoordinated carboxyl­ate O atoms of neighboring mol­ecules, and aromatic π–π stacking inter­actions between neighboring phenanthroline rings.