Tetrakis(μ‐guanidino­acetic acid‐κ2O:O′)­bis­[(nitrato‐κO)copper(II)]

The title compound, [Cu₂(NO₃)₂(C₃H₇N₃O₂)₄], forms a centrosymmetric dimer, with the two Cu²⁺ ions separated by 2.6525 (6) Å. The asymmetric unit contains a Cu atom coordinated to two guanidino­acetic acid ligands (via one carboxyl­ate O atom from each ligand) and to a nitrate group. The inversion centre in P generates the entire mol­ecule, in which each Cu atom is coordinated to four carboxyl­ate and to one nitrate O atom; ignoring the Cu—Cu separation, the geometry about each Cu atom is square pyramidal. The amino acid ligand is in the zwitterionic form. Strong N—H?O hydrogen bonds lead to a three‐dimensional supramolecular structure, in which the N?O distances are in the range 2.931 (4)–3.278 (3) Å, with N—H?O angles ranging from 128 to 170°.     

catena‐Poly[[tetra­kis(μ‐propionato‐κ2O:O′)dicopper(II)]‐μ‐3‐pyridylmethanol‐κ2N:O‐[bis­(propionato‐κO)bis­(3‐pyridylmethanol‐κN)copper(II)]‐μ‐3‐pyridylmethanol‐κO:N]

The title compound, [Cu₃(C₃H₅O₂)₆(C₆H₇NO)₄]_n, is composed of polymeric chains formed by alternating centrosymmetric Cu₂(μ‐CH₃CH₂CO₂)₄ and Cu(C₃H₅O₂)₂(C₆H₇NO)₂ units. These elemental units are linked by two bridging 3‐pyridylmethanol (3PM) ligands. The Cu₂(μ‐CH₃CH₂CO₂)₄ group presents a centrosymmetric tetra­bridged structure with four syn–syn bridging propionate ligands to which two 3PM mol­ecules are bonded (through N), occupying the apical positions of each square‐pyramidal polyhedron around the Cu^II ions. The remaining mononuclear group is centred around a third Cu^II ion, which lies on a symmetry centre and is bound to two monodentate propionate groups (through O), two monodentate 3PM mol­ecules (through N) and two bridging 3PM mol­ecules (through O), thus completing a square‐bipyramidal CuO₂N₂O₂ coordination.     

catena‐Poly[[(acetato‐κ2O,O′)triaquabarium(II)]‐μ3‐acetato‐κ4O:O,O′:O′]

The present form of barium acetate, formulated as [Ba(C₂H₃O₂)₂(H₂O)₃]_n, is the largest reported hydrate of the salt and this leads to a distinct structural behaviour setting it apart from the rest of the family. The compound is a linear polymer with a nine‐coordinate Ba(O_aqua)₃(O_acetate)₆ monomer unit. The non‐H part of the structure is ordered according to C2/m symmetry, while the disordered water H atoms only abide by this symmetry in a statistical sense. Each molecule is halved by a mirror plane bisecting the Ba centre, one water molecule and one acetate ligand, while containing the other acetate ligand. The chains are interconnected by a disordered water–water/acetate O—H...O hydrogen‐bonding network involving all water H atoms. The structure and stability of this phase are compared with the other known acetates of barium which differ in the degree of hydration.     

Bis(μ‐diphenyl­phosphinato‐κ2O:O′)bis­[aqua­(diphenyl­phosphinato‐κO)bis­(pyridine‐κN)cobalt(II)]

In the centrosymmetric title compound, [Co₂(C₁₂H₁₀O₂P)₄(C₅H₅N)₄(H₂O)₂], each approximately octa­hedral Co atom features two trans‐coordinated pyridine mol­ecules, one water mol­ecule, a terminally coordinated monodentate diphenyl­phosphinate ligand, and two bidentate diphenyl­phosphinate ligands that bridge the two Co atoms across a centre of inversion to form a dimeric binuclear complex. The discrete mol­ecules are linked by double hydrogen bonds between the terminally coordinated diphenyl­phosphinate ligand and the water mol­ecule to form a continuous chain along the crystallographic b axis.     

μ2‐Acetato‐κ2O:O′‐tris(μ2‐ferrocenecarboxylato‐κ2O:O′)bis[(N,N‐dimethylformamide‐κO)copper(II)]

The title compound, [Cu₂Fe₃(C₅H₅)₃(C₂H₃O₂)(C₆H₄O₂)₃(C₃H₇NO)₂], belongs to the classic dimeric paddle‐wheel structure type. It is an unusual example in that it contains two different carboxylate groups, viz. ferrocenecarboxylate and acetate. With three ferrocenecarboxylate groups and only one acetate group bridging the two Cu centres, a noncentrosymmetric molecular arrangement results.     

Poly­[[bis­(pyridine‐κN)copper(II)]‐μ3‐5‐hydroxy­isophthalato‐κ3O:O′:O′′]

In the title compound, [Cu(C₈H₄O₅)(C₅H₅N)₂]_n or [Cu(OH‐BDC)(py)₂]_n (where OH‐H₂BDC is 5‐hydroxy­isophthalic acid and py is pyridine), the Cu atoms are coordinated by two N atoms from the pyridine ligands and by three O atoms from hydroxy­isophthalate ligands in a highly distorted triangular bipyramidal environment, with Cu—O distances in the range 1.941 (4)–2.225 (5) Å and Cu—N distances of 2.014 (6) and 2.046 (6) Å. The [Cu(OH‐BDC)]_n two‐dimensional network is built up from interlocking 22‐, 15‐ and eight‐membered rings via sharing of Cu atoms and O—H⋯O hydrogen bonds. Consolidation of the packing structure is achieved by edge‐ or point‐to‐face C—H⋯π interactions and offset or slipped π–π stacking interactions.     

Bis(μ‐acetato‐κ3O,O′:O′)bis[bis(acetato‐κ2O,O′)diaquadysprosium(III)] tetrahydrate

The title compound, [Dy₂(C₂H₃O₂)₆(H₂O)₄]·4H₂O, crystallizes in the form of dimeric units related by an inversion centre. Each cation is nine‐coordinate, binding to two water mol­ecules and three acetate groups, two of which are bidentate and the third tridentate. This last acetate group acts as a bridge between neighbouring metal atoms, leading to an intradimer Dy?Dy separation of 4.170 (1) Å.     

Bis(1‐ferrocenylbutane‐1,3‐dionato‐κ2O,O′)copper(II) and bis­(1,3‐diferrocenylpropane‐1,3‐dionato‐κ2O,O′)­copper(II)

The title compounds, [CuFe₂(C₅H₅)₂(C₉H₈O₂)₂], (I), and [CuFe₄(C₅H₅)₄(C₁₃H₉O₂)₂], (II), are four‐coordinate square‐planar copper(II) complexes with two bidentate 1‐ferrocenylbutane‐1,3‐dionate or 1,3‐diferrocenylpropane‐1,3‐dionate ligands, respectively. The copper ion in (I) lies on an inversion centre, with one‐half of the mol­ecule in the asymmetric unit, while in (II), there are two independent half mol­ecules in the asymmetric unit, with the copper ions also situated on inversion centres. The ferrocene substituents in (I) are in an anti arrangement. The mol­ecules assemble in the crystal structure in layers with ferrocene groups at the surface. The pairs of ferrocene substituents on each ligand in complex (II) are syn and these adopt an anti arrangement with respect to the pair on the other diketonate ligand. As found in (I), complexes assemble in a layered structure with ferrocene‐coated surfaces.     

catena‐Poly[[diaquabis(2‐chloronicotinato‐κ2O,O′)cadmium(II)]‐μ‐2‐chloronicotinato‐κ3O,O′:N]

In the title neutral coordination polymer, [Cd(C₆H₃ClNO₂)₂(H₂O)₂]_n, each Cd^II ion is coordinated by one N and four O atoms from three 2‐chloro­nicotinate ligands and by two aqua ligands, defining a distorted monocapped octahedral coordination geometry. Adjacent Cd atoms are linked by the pyridyl N atom and the bidentate carboxyl­ate functional group of a 2‐­chloro­nicotinate ligand, forming a one‐dimensional infinite chain along the b axis. The Cd⋯Cd distance is 8.112 (3) Å. These chains are linked by O—H⋯O and O—H⋯N hydrogen bonds into a three‐dimensional network structure.     

catena‐Poly[[bis(nitrato‐κ2O,O′)copper(II)]‐μ‐propane‐1,3‐diylbis(diphenylphosphine oxide)‐κ2O:O′]

The structure of the title complex, [Cu(NO₃)₂(C₂₇H₂₆O₂P₂)]_n, consists of polymeric chains formed by propane‐1,3‐diylbis(diphenylphosphine oxide) ligands bridging between metal centres. The Cu atom lies on a twofold rotation axis and a further symmetry centre bisects the bridging bisphosphine dioxide ligand. The CuO₆ coordination geometry is a distorted octahedron, with the bidentate chelating nitrate groups adopting a cis configuration.     

catena‐Poly­[bis­[(2,2‐bi­pyridine‐κ2N,N′)­copper(II)]‐μ4‐1,2,4,5‐benzene­tetra­carboxyl­ato‐κ4O1:O2:O3:O4]

In the title complex, [Cu₂(C₁₀H₂O₈)(C₁₀H₈N₂)₂]_n, the Cu^II cation has a four‐coordinated environment, completed by two carboxyl O atoms belonging to two 1,2,4,5‐benzene­tetra­carboxyl­ate anions (TCB⁴⁻) and two N atoms from one 2,2′‐bi­pyridine (2,2′‐bipy) ligand, forming a distorted square‐planar geometry. The [Cu(2,2′‐bipy)]²⁺ moieties are bridged by TCB⁴⁻ anions, which lie about inversion centres, forming an infinite one‐dimensional coordination polymer with a double‐chain structure along the a axis. A two‐dimensional network structure is formed via a face‐to‐face π–π interaction between the 2,2′‐bipy rings belonging to two adjacent double chains, at a distance of approximately 3.56 Å.     

A dinuclear CoII complex: bis(μ‐di­hydrogen phosphato‐κ2O:O′)­bis­[(bipyridine‐κ2N,N′)(di­hydrogen phosphato‐κO)­cobalt(II)]

The title compound, [Co₂(H₂PO₄)₄(C₁₀H₈N₂)₂], is dinuclear, centred on a symmetry centre of the P space group. Each Co atom has a distorted square‐pyramidal coordination involving two N atoms from a bi­pyridine mol­ecule and three O atoms from two bridging and one terminal di­hydrogen ortho­phosphate anion. The molecular structure and packing are stabilized by intermolecular hydrogen‐bond interactions.     

Tetra‐μ‐acetato‐O:O′‐bis­[(7‐aza­indole‐N)­copper(II)]

The title complex, [Cu₂(C₂H₃O₂)₄(C₇H₆N₂)₂], shows a binuclear cage structure having an inversion centre. There are intramolecular N—H?O hydrogen bonds between the 7‐aza­indole ligands and the bridging acetate O atoms.     

(2,2′‐Biquinoline‐κ2N,N′)bis(nitrato‐κ2O,O′)copper(II)

In the title monomer, [Cu(NO₃)₂(C₁₈H₁₂N₂)], the six‐coordinated Cu^II atom lies on a twofold axis which bisects one of the ligands (a chelating biquinoline) and duplicates the remaining ligand, a chelating nitrate. The latter binds in a very asymmetric way, consistent with a Jahn–Teller distortion in the coordination polyhedron which, due to the triple chelation, is extremely distorted and difficult to describe in terms of any regular model.     

Bis(μ‐succinato‐O,O′:O′′,O′′′)bis[bis(2‐amino‐1,3‐benzothiazole‐N3)copper(II)]

In the title dimeric complex, [Cu₂(C₄H₄O₄)₂(C₇H₆N₂S)₄], which possesses a centre of symmetry, the Cu atoms are enclosed in a 14‐membered ring. They adopt a distorted square‐bipyramidal (4+2) coordination. The four closest donor atoms are two N atoms of 2‐amino­benzo­thiazole ligands and two O atoms of the succinate carboxylate groups. They form a square‐planar cis arrangement, with an average Cu—N distance of 2.003 (3) Å and Cu—O distances of 1.949 (3) and 1.965 (3) Å. Two longer Cu—O bonds of 2.709 (3) and 2.613 (3) Å involving the remaining O atoms of the carboxylate groups complete the sixfold coordination of the Cu atoms. The H atoms of each amino group of the 2‐amino­benzo­thiazole molecules form intra‐ and inter­molecular N—H?O hydrogen bonds. A nearly perpendicular inter­molecular C—H?Cg interaction (Cg is the centroid of the imidazole ring) is observed. The intramolecular Cu?Cu distance is 6.384 (2) Å.     

{μ‐N,N′‐Bis[3‐(dimethyl­amino)prop­yl]­oxamidato(2–)‐κ6N,N′,O′:N′′,N′′′,O}­bis­[(1H‐imidazole‐κN3)(methanol‐κO)copper(II)] bis­(perchlorate)

The structure of the title compound, [Cu₂(C₁₂H₂₄N₄O₂)(C₃H₄N₂)₂(CH₄O)₂](ClO₄)₂ or [Cu₂(dmoxpn)(HIm)₂(CH₃OH)₂](ClO₄)₂, where dmoxpn is the dianion of N,N′‐bis­[3‐(dimethyl­amino)prop­yl]oxamide and HIm is imidazole, consists of a centrosymmetric trans‐oxamidate‐bridged copper(II) binuclear cation, having an inversion centre at the mid‐point of the central C—C bond, and two perchlorate anions. The Cu^II atom has square‐pyramidal coordination geometry involving two N atoms and an O atom from the dmoxpn ligand, an N atom from an imidazole ring, and an O atom from a methanol mol­ecule. The crystal structure is stabilized by O—H⋯O, N—H⋯O and C—H⋯O hydrogen bonds and imidazole π–π stacking inter­actions to form a three‐dimensional supra­molecular array.     

Di‐μ‐aqua‐bis­[(N‐salicyl­idene‐β‐alaninato‐κ3O,N,O′)copper(II)] urea disolvate

Crystals of the title compound, [Cu₂(C₁₀H₉NO₃)₂(H₂O)₂]·2CH₄N₂O, consist of two (N‐salicyl­idene‐β‐alaninato‐κ³O,N,O′)copper(II) coordination units bridged by two water moieties to form a dimer residing on a crystallographic inversion center, along with two uncoordinated urea mol­ecules. The Cu^II atom has square‐pyramidal coordination, with three donor atoms of the tridentate Schiff base and an O atom of the bridging aqua ligand in the basal plane. The axial position is occupied by the second bridging water ligand at a distance of 2.5941 (18) Å. Hydro­gen bonds between mol­ecules of urea and the neighboring dimer units lead to the formation of a two‐dimensional grid of mol­ecules parallel to [101]. The superposition of the normals of the pyramidal base planes in the direction [100] indicates possible π–π interactions between the neighboring units.     

Poly[triaqua(μ4‐4‐carboxybenzenesulfonato‐κ4O:O′:O′′:O′′′)(4‐carboxybenzenesulfonato‐κO)strontium(II)]

This study presents the coordination modes and two‐dimensional network of a novel strontium(II) coordination polymer, [Sr(C₇H₅O₅S)₂(H₂O)₃]_n. The eight‐coordinate Sr²⁺ ion is in a distorted bis‐disphenoidal coordination environment, surrounded by four sulfonate and one carboxyl O atom from five benzenesulfonate ligands, two of which are symmetry unique, and by three O atoms from three independent aqua ligands. The compound exhibits a monolayer structure with coordination bonds within and hydrogen bonds between the layers. The μ₄ acid ligand bridges the metal ions in two dimensions to form a thick undulating monolayer with a hydrophobic interior and hydrophilic surfaces. A second independent monoanion is arranged outward from both sides of the monolayer and serves to link adjacent monolayers via carboxyl–water and water–carboxyl hydrogen bonds.     

Poly­[methyl­ammonium tris(μ2‐form­ato‐κ2O:O′)­cobalt(II)]

The structure of the title compound, {(CH₆N)[Co(CHO₂)₃]}_n, consists of a three‐dimensional net of central Co^II ions connected via formate (methane­diolate) bridges. The negative charge is compensated by protonated methyl­amine cations. The CoO₆ chromophores form slightly distorted octahedra, which are bridged by C atoms of formate groups. The central Co atom lies on an inversion center and most of the other atoms lie on an m plane.     

catena‐Poly­[[di­aqua­(nicotinato‐κ2O,O′)­cadmium(II)]‐μ‐nicotinato‐κ3N:O,O′]

The title compound, [Cd(C₆H₄NO₂)₂(H₂O)₂]_n, forms a one‐dimensional chain structure based on a Cd atom with approximate pentagonal bipyramidal coordination geometry and two nicotinate ligands in different coordination modes. One acts as a tridentate ligand, chelating one Cd atom through the carboxyl­ate group while simultaneously binding to a second symmetry‐related Cd atom through the pyridine N atom; the other acts only as a bidentate ligand through its carboxyl­ate group. Hydro­gen bonds utilizing the coordinated water mol­ecules, uncoordinated nitro­gen and carboxyl­ate O atoms as acceptors link the chains.