μ‐Acetato‐1:2κ2O:O′‐diacetato‐1κ2O,O′;2κO‐bis(di‐2‐pyridylamine)‐1κ2N,N′;2κ2N,N′‐isothiocyanato‐2κN‐dicopper(II)

In the title dinuclear acetate‐bridged complex, [Cu₂(C₂H₃O₂)₃(NCS)(C₁₀H₉N₃)₂], the two Cu atoms are five‐coordinated, with a basal plane consisting of two N atoms of a di‐2‐pyridylamine (dpyam) ligand and two O atoms of two different acetate ligands. The axial positions of these Cu atoms are coordinated to N and O atoms from thio­cyanate and acetate mol­ecules, respectively, leading to a distorted square‐pyramidal geometry with τ values of 0.30 and 0.22. Both Cu^II ions are linked by an acetate group in the equatorial–equatorial positions and have syn–anti bridging configurations. Hydrogen‐bond inter­actions between the amine H atom and the coordinated and uncoordinated O atoms of the acetate anions generate an infinite one‐dimensional chain.     

A novel helical copper complex: catena‐poly[[[aquacopper(II)]‐μ‐N‐(3‐carboxy‐2‐oxidobenzylidene‐κO2)glycinato‐κ3N,O′:O′] monohydrate]

In the polymeric title compound, {[Cu(C₁₀H₇NO₅)(H₂O)]·H₂O}_n, the Cu atom adopts a square‐based pyramidal coordination involving a N,O,O′‐tridentate glycine dianionic ligand, a water O atom and an apical bridging carboxylate O atom from an adjacent ligand. The title compound also adopts a carboxylate‐bridged chain structure. The molecular chain propagates in a helical fashion along the b axis of the monoclinic unit cell. Neighbouring chains are linked together to form a three‐dimensional network via hydrogen‐bonding interactions between coordinated and uncoordinated water molecules and O atoms of the bridging carboxylate groups.     

Bis(2‐amino‐1H‐benzimidazol‐3‐ium) tetrakis(μ‐but‐2‐enoato)‐κ4O:O′;κ3O,O′:O;κ3O:O,O′‐bis[bis(but‐2‐enoato‐κ2O,O′)holmium(III)]

The title ionic compound, (C₇H₈N₃)₂[Ho₂(C₄H₅O₂)₈], is constructed from two almost identical independent centrosymmetric anionic dimers balanced by two independent 2‐amino‐1H‐benzimidazol‐3‐ium (Habim⁺) cations. The asymmetric part of each dimer is made up of one Ho^III cation and four crotonate (crot or but‐2‐enoate) anions, two of them acting in a simple η²‐chelating mode and the remaining two acting in two different μ₂:η² fashions, viz. purely bridging and bridging–chelating. Symmetry‐related Ho^III cations are linked by two Ho—O—Ho and two Ho—O—C—O—Ho bridges which lead to rather short intracationic Ho...Ho distances [3.8418 (3) and 3.8246 (3) Å]. In addition to the obvious Coulombic interactions linking the cations and anions, the isolated [Ho₂(crot)₈]²⁻ and Habim⁺ ions are linked by a number of N—H...O hydrogen bonds, in which all N—H groups of the cation are involved as donors and all (simple chelating) crot O atoms are involved as acceptors. These interactions result in compact two‐dimensional structures parallel to (110), which are linked to each other by weaker π–π contacts between Habim⁺ benzene groups.     

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.     

Di‐μ‐formato‐1κ2O:2κ2O′‐di‐μ‐pyridin‐2‐olato‐1κO:2κN;1κN:2κO‐bis­[(2‐pyridone‐κO)copper(II)] acetonitrile 1.02‐solvate

In the title compound, [Cu₂(CHO₂)₂(C₅H₄NO)₂(C₅H₅NO)₂]·1.02CH₃CN, the dimeric unit is centrosymmetric, with two bidentate pyridin‐2‐olate and two bidentate formate syn–syn bridges, and two apical 2‐pyridone ligands coordinated through the O atoms. The N atom from the apical 2‐pyridone ligand is a donor of a hydrogen bond to the O atom of the bridging pyridinolate ligand of the same complex. The coordination polyhedron of the Cu atom is a distorted square pyramid.     

(μ‐1,2‐Dimethoxyethane‐κ2O:O′)bis[(1,2‐dimethoxyethane‐κ2O,O′)tris(1,1,1,5,5,5‐hexafluoro‐4‐oxopent‐2‐en‐2‐olato‐κ2O,O′)cerium(III)]

A previous analysis [Fatila et al. (2012). Dalton Trans. 41 , 1352–1362] of the title complex, [Ce₂(C₅HF₆O₂)₆(C₄H₁₀O₂)₃], had identified it as Ce(hfac)₃(dme)_1.5 according to the ¹H NMR integration [hfac = 1,1,1,5,5,5‐hexafluoroacetylacetonate (1,1,1,5,5,5‐hexafluoro‐4‐oxopent‐2‐en‐2‐olate) and dme = 1,2‐dimethoxyethane]; however, it was not possible to determine the coordination environment unambiguously. The structural data presented here reveal that the complex is a binuclear species located on a crystallographic inversion center. Each Ce^III ion is coordinated to three hfac ligands, one bidentate dme ligand and one monodentate (bridging) dme ligand, thus giving a coordination number of nine (CN = 9) to each Ce^III ion. The atoms of the bridging dme ligand are unequally disordered over two sets of sites. In addition, in two of the –CF₃ groups, the F atoms are rotationally disordered over two sets of sites. This is the first crystal structure of a binuclear lanthanide β‐diketonate with a bridging dme ligand.     

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‐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.     

Aqua(oxydiacetato‐κ3O,O′,O′′)(pyridine‐3‐carboxamide‐κN1)copper(II) sesquihydrate

In the monomeric title compound, [Cu(C₄H₄O₅)(C₆H₆N₂O)(H₂O)]·1.5H₂O, the Cu^II cation is bound in a square‐pyramidal coordination to a tridentate oxydiacetate (ODA) ligand, a monodentate pyridine‐3‐carboxamide (p3ca) ligand and one aqua ligand, where the two organic ligands form the basal plane and the water O atom occupies the unique apical site. The ODA ligand presents a slight out‐of‐plane puckering in its central ether O atom, while the p3ca ligand is essentially planar. The availability of efficient donors and acceptors for hydrogen bonding results in the formation of strongly linked hydrogen‐bonded bilayers parallel to (101), with an interplanar distance of 3.18 (1) Å and a stacking separation between the bilayers of 3.10 (1) Å, both of them governed by extended π–π interactions. The disordered nature of the solvent water molecules around inversion centres is discussed. The monoaqua compound is compared with the octahedral diaqua analogue, [Cu(C₄H₄O₅)(C₆H₆N₂O)(H₂O)₂], reported recently [Perec & Baggio (2009). Acta Cryst. C 65 , m296–m298].     

catena‐Poly[[[aqua(ethylenediamine‐κ2N,N′)(nitrato‐κO)copper(II)]‐μ‐4,4′‐dithiodipyridine‐κ2N:N′] nitrate monohydrate]

The title compound, {[Cu(NO₃)(C₂H₄N₂)(C₁₀H₈N₂S₂)(H₂O)]NO₃·H₂O}_n, is composed of a one‐dimensional linear coordination polymer involving cis‐protected copper(II) ions and a 4,4′‐dithiodipyridine bridging ligand. The polymeric chains run along the c‐axis direction. N—H...O and O—H...O hydrogen bonds involving the coordinating amine groups, nitrate ions and water molecules, as well as cocrystallized noncoordinating nitrate ions and water molecules, generate a three‐dimensional structure.     

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.     

Poly[[[diaqua­dioxouranium(VI)]‐μ3‐nitriliotriacetato‐κ3O:O′:O′′] trihydrate]

The basic units in the structure of the title compound, {[UO₂(C₆H₇NO₆)(H₂O)₂]·3H₂O}_n, are ribbons in which every UO₂²⁺ cation is coordinated in a monodentate manner to three tridentate‐bridging nitriliotriacetate dianions. Hydrogen bonds bind the ribbons into a three‐dimensional structure.     

Bis(2,6‐diamino‐1H‐purin‐3‐ium) di‐μ‐croconato‐κ3O,O′:O′′;κ3O:O′,O′′‐bis[tetraaqua(croconato‐κ2O,O′)neodymium(III)]

The structure of the ionic title compound, (C₅H₇N₆)₂[Nd₂(C₅O₅)₄(H₂O)₈], consists of anionic dimers built around an inversion centre and is made up of an Nd^III cation, two croconate (croco) dianions and four water molecules (plus their inversion images), with two noncoordinated symmetry‐related 2,6‐diamino‐1H‐purin‐3‐ium (Hdap⁺) cations providing charge balance. Each Nd^III atom is bound to nine O atoms from four water and three croco units. The coordination polyhedron has the form of a rather regular monocapped square antiprism. The croconate anions are regular and the Hdap⁺ cation presents a unique, thus far unreported, protonation state. The abundance of hydrogen‐bonding donors and acceptors gives rise to a complex packing scheme consisting of dimers interlinked along the three crystallographic directions and defining anionic `cages' where the unbound Hdap⁺ cations lodge, linking to the mainframe via (N—H)_Hdap...O_water/croco and (O—H)_water...N_Hdap interactions.     

Potassium,rubidium and ammonium salts of μ‐(formato‐κ2O:O′)‐μ‐oxido‐bis[oxidobis(peroxido‐κ2O,O′)molybdate(VI)]

The unit‐cell parameters of the three title salts, namely, tripotassium, K₃[Mo₂(CHO₂)O₃(O₂)₄], trirubidium, Rb₃[Mo₂(CHO₂)O₃(O₂)₄], and triammonium μ‐(formato‐κ²O:O′)‐μ‐oxido‐bis[oxidobis(peroxido‐κ²O,O′)molybdate(VI)], (NH₄)₃[Mo₂(CHO₂)O₃(O₂)₄], which were all crystallized at pH 3, are quite similar, but the potassium and rubidium salt structures are noncentrosymmetric, whereas that of the ammonium salt is centrosymmetric. Formate acts as an O:O′‐bridging ligand in the complex anion and is bound to a μ‐oxido‐bis(oxidodiperoxidomolybdate) unit.     

(μ‐C‐meso‐5,5,7,12,12,14‐Hexa­methyl‐1,4,8,11‐tetra­aza­cyclo­tetra­decane‐N‐acetato‐1κ5N,N′,N′′,N′′′,O:2κO′)­tetra­chloro‐1κCl,2κ3Cl‐cobalt(III)­zinc(II)

The crystal structure of the title compound, [CoCl(C₁₈H₃₇N₄O₂){ZnCl₃}], has been determined by X‐ray diffraction.C‐meso‐5,5,7,12,12,14‐Hexa­methyl‐1,4,8,11‐tetra­aza­cyclotetradecane‐N‐acetate acts as a bridging ligand to coodinate with Co^III and Zn^II ions. The Co^III ion is six‐coordinate in a nearly octahedral environment provided by one Cl atom, four N atoms of the bridging ligand, and one O atom. The Zn^II ion is four‐coordinate in a distorted tetrahedral environment completed by three Cl atoms and an O atom of the bridging ligand.     

Unusual O‐coordination of caffeine in tetra­kis(μ‐3,5‐dinitro­benzoato‐κ2O:O′)bis­[(caffeine‐κO)copper(II)]

The title compound {systematic name: tetra­kis(μ‐3,5‐dinitro­benzoato‐κ²O:O′)bis­[(3,7‐dihydro‐1,3,7‐trimethyl‐1H‐purine‐2,6‐dione‐κO²)copper(II)]}, [Cu₂(C₇H₃N₂O₆)₄(C₈H₁₀N₄O₂)₂], consists of paddle‐wheel dimeric tetra­kis(μ‐3,5‐dinitro­benzoato‐κ²O:O′)dicopper(II) units with O‐coordinated caffeine mol­ecules in both apical positions. The entire dimeric mol­ecule lies on a tetra­gonal inversion axis, and thus one nitro­benzoate anion with one Cu atom in a special position belong to the independent part of the mol­ecule. The caffeine ligand bonded to the Cu atom is disordered on a local twofold non‐crystallographic axis coincident with the axis. A π–π stacking inter­action is observed between the caffeine rings and adjacent symmetry‐related benzene rings of the 3,5‐dinitro­benzoate anions.     

Bis(2‐chloro‐5‐methylpyridine‐κN)bis(nitrato‐κ2O,O′)copper(II)

In the molecule of the title compound, [Cu(NO₃)₂(C₆H₆ClN)₂], the Cu atom lies on an inversion centre and is six‐coordinated by two pyridine N atoms and four nitrate O atoms in trans positions. The nitrate acts as an unsymmetrical bidentate ligand. The coordination geometry is octahedral, with the Cu—N and the two Cu—O distances being 1.9939 (16), 2.0246 (16) and 2.4866 (19) Å, respectively. There are five types of C—H⋯O hydrogen bonds. Two of these generate two‐dimensional molecular networks in the direction of the a axis, and the others connect adjacent molecular networks.     

Low‐dimensional compounds containing cyano groups. II. catena‐Poly[[(2,2′‐bipyridine‐κ2N:N′)(dicyanamido‐κN)copper(II)]‐μ‐dicyanamido‐κ2N:N′]

The crystal structure of the title compound, [Cu(C₂N₃)₂(C₁₀H₈N₂)]_n, is formed by neutral zigzag chains of the [–NC–N–CN–Cu{(bpy)N(CN)₂}–NC–N–CN–] type run­ning along the c axis (bpy is 2,2′‐bi­pyridine). The Cu atoms in the chains are pentacoordinated in the form of a distorted tetragonal pyramid, with a CuN₅ chromophore. The coordination sites are occupied by two N atoms of one bpy mol­ecule in the basal plane [Cu—N 2.018 (4) and 2.025 (2) Å] and by three terminal N atoms of two dicyan­amide ligands. One of the dicyan­amide ligands is coordinated in a monodentate fashion through a nitrile N atom in the basal plane [Cu—N 1.963 (4) Å]. The second acts as an end‐to‐end bridging ligand to a neighbouring Cu atom and is coordinated by one nitrile N atom in the basal plane [Cu—N 2.001 (2) Å], while the second nitrile N atom occupies the apical position [Cu—N 2.159 (2) Å] and originates from the bridge connecting another Cu atom. The shortest intrachain Cu?Cu distance is 8.212 (1) Å, as a consequence of the large bridging ligand, whereas the minimum interchain distance between Cu atoms is only 5.77 (7) Å, because of the interdigitation of the chains.     

Bis(2‐amino‐2‐thiazolinium) tetra‐μ‐formato‐κ8O:O′‐bis[(formato‐κO)copper(II)]

In the title dimeric compound, (C₃H₇N₂S)₂[Cu₂(CHO₂)₆], each Cu^II atom has a square‐pyramidal coordination, with the nonbridging formate ion at the apical position. The complex anion is located on a crystallographic inversion centre, with a Cu...Cu separation of 2.6566 (4) Å. 2‐Amino‐2‐thiazolinium cations connect complex anions via hydrogen bonds to form a ribbon running along the a axis.     

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.