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.     

Poly[bis(μ3‐5′‐carboxy‐2,2′‐bipyridine‐5‐carboxylato‐κ4O:N,N′:O′)lead(II)]

The title compound, [Pb(C₁₂H₇N₂O₄)₂]_n, obtained by reaction of Pb(NO₃)₂ and 2,2′‐bipyridine‐5,5′‐dicarboxylic acid (H₂bptc) under hydrothermal conditions, has a structure in which the unique Pb^II cation sits on a twofold axis and is octa‐coordinated by four O‐atom donors from four Hbptc⁻ ligands and four N‐atom donors from two Hbptc⁻ ligands in a distorted dodecahedral geometry. With each Pb^II cation connected to six Hbptc⁻ ligands and each Hbptc⁻ ligand bridging three Pb^II cations, a three‐dimensional polymeric structure is formed. From a topological point of view, the three‐dimensional net is binodal, with six‐connected (the Pb^II cation) and three‐connected (the Hbptc⁻ ligand) nodes, resulting in a distorted rutile (4².8)₂(4⁴8⁹12²) topology.     

Tris(2,2′‐bioxazoline‐κ2N,N′)copper(II) diperchlorate and tris(2,2′‐bioxazoline‐κ2N,N′)­nickel(II) diperchlorate

In the two isomorphous title compounds, viz. tris­[2,2′‐bi(4,5‐di­hydro‐1,3‐oxazole)‐κ²N,N′]copper(II) diperchlorate, [Cu(C₆H₈N₂O₂)₃](ClO₄)₂, (I), and tris­[2,2′‐bi(4,5‐di­hydro‐1,3‐oxazole)‐κ²N,N′]­nickel(II) diperchlorate, [Ni(C₆H₈N₂O₂)₃](ClO₄)₂, (II), the M^II ions each have a distorted octahedral coordination geometry formed via six N atoms from three 2,2′‐bioxazoline ligands. For each ligand, the two five‐membered rings are nearly coplanar. It is noteworthy that the Jahn–Teller effect is stronger in (I) than in (II). The three‐dimensional supramolecular structures of (I) and (II) are formed via weak hydrogen‐bonding interactions between O atoms from per­chlorate anions and H atoms from 2,2′‐bioxazoline ligands.     

A three‐dimensional framework in 2,2′‐biimidazolium bis(2,2′‐biimidazole‐κ2N,N′)bis(biphenyl‐2,4′‐dicarboxylato‐κO)manganese(II) hexahydrate

In the title salt, (C₆H₈N₄)[Mn(C₁₄H₈O₄)₂(C₆H₆N₄)₂]·6H₂O, the Mn^II atom lies on an inversion centre and is coordinated by four N atoms from two 2,2′‐biimidazole (biim) ligands and two O atoms from two biphenyl‐2,4′‐dicarboxylate (bpdc) anions to give a slightly distorted octahedral coordination, while the cation lies about another inversion centre. Adjacent [Mn(bpdc)₂(biim)₂]²⁻ anions are linked via two pairs of N—H...O hydrogen bonds, leading to an infinite chain along the [100] direction. The protonated [H₂biim]²⁺ moiety acts as a charge‐compensating cation and space‐filling structural subunit. It bridges two [Mn(bpdc)₂(biim)₂]²⁻ anions through two pairs of N—H...O hydrogen bonds, constructing two R₂²(9) rings, leading to a zigzag chain in the [2] direction, which gives rise to a ruffled set of [H₂biim]²⁺[Mn(bpdc)₂(biim)₂]²⁻ moieties in the [01] plane. The water molecules give rise to a chain structure in which O—H...O hydrogen bonds generate a chain of alternating four‐ and six‐membered water–oxygen R₄²(8) and R₆⁶(12) rings, each lying about independent inversion centres giving rise to a chain along the [100] direction. Within the water chain, the (H₂O)₆ water rings are hydrogen bonded to two O atoms from two [Mn(bpdc)₂(biim)₂]²⁻ anions, giving rise to a three‐dimensional framework.     

Tetrakis(2,2′‐bipyridine‐κ2N,N′)­tetrakis(μ‐salicyl­ato‐κ3O,O′:O′′)‐quadro‐tetrazinc(II) decahydrate

The title compound, [Zn₄(C₇H₄O₃)₄(C₁₀H₈N₂)₄]·10H₂O, crystallizes as a centrosymmetric tetranuclear cyclic complex containing four Zn^II atoms bridged by four carboxyl­ate groups from salicyl­ate ligands, with a syn–anti configuration. Each Zn^II atom has a distorted trigonal–bipyramidal coordination geometry, formed by two N atoms of a 2,2′‐bipyridine ligand and three O atoms from two salicyl­ate ligands. The complex is stabilized by intramolecular π–π interactions between pairs of bi­pyridine rings and a 16‐membered gear‐wheel‐shaped cyclic framework. The hydrogen‐bonding network is formed via the water mol­ecules.     

(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.     

catena‐Poly[[dicyanamido(5,5′‐dimethyl‐2,2′‐bipyridine‐κ2N,N′)copper(II)]‐μ‐dicyanamido‐κ2N1:N5]

In the crystal structure of the title compound, [Cu(C₂N₃)₂(C₁₂H₁₂N₂)]_n, the Cu^II atom adopts a distorted square‐pyramidal geometry, the basal plane of which is formed by two N atoms of the bi­pyridine ligand, one N atom of a bidentate dicyan­amide anion and one N atom of a monodentate dicyan­amide anion [Cu—N = 1.9760 (15)–2.0157 (15) Å]. The apical position is occupied by an N atom of a bidentate dicyan­amide anion, located 2.2468 (16) Å from the Cu atom, thus forming a one‐dimensional polymeric chain.     

Triaqua(2,2′‐bipyridine‐κ2N,N′)(nitrato‐κO)manganese(II) nitrate

The crystal structure of the title compound, [Mn(NO₃)(C₁₀H₈N₂)(H₂O)₃]NO₃, contains a monomeric [Mn(NO₃)(bpy)(H₂O)₃]⁺ cation (bpy is 2,2′‐bi­pyridine) and a nitrate anion. The Mn^II ion is coordinated by one chelating bpy [Mn—N 2.241 (3) and 2.259 (3) Å], three water mol­ecules [Mn—O 2.120 (3)–2.188 (3) Å] and a nitrate ligand [Mn—O 2.228 (2) Å] in a distorted octahedral geometry. There are O?H—O hydrogen‐bonding interactions between the ligated water mol­ecules and the ligated and unligated nitrate anions, resulting in double columns of stacked cations and anions.     

μ‐{N,N′‐Bis[2‐(dimethyl­amino)ethyl]oxamidato(2–)}‐1κ2O,O′:2κ4N,N′,N′′,N′′′‐bis­(4,4′‐dimethyl‐2,2′‐bipyridine‐1κ2N,N′)dinickel(II) bis­(perchlorate)

In the crystal structure of the title complex, [Ni₂(C₁₀H₂₀N₄O₂)(C₁₂H₁₂N₂)₂](ClO₄)₂ or [Ni(dmaeoxd)Ni(dmbp)₂](ClO₄)₂ {H₂dmaeoxd is N,N′‐bis­[2‐(dimethyl­amino)ethyl]oxamide and dmbp is 4,4′‐dimethyl‐2,2′‐bipyridine}, the deprotonated dmaeoxd²⁻ ligand is in a cis conformation and bridges two Ni^II atoms, one of which is located in a slightly distorted square‐planar environment, while the other is in an irregular octa­hedral environment. The cation is located on a twofold symmetry axis running through both Ni atoms. The dmaeoxd²⁻ ligands inter­act with each other via C—H⋯O hydrogen bonds and π–π inter­actions, which results in an extended chain along the c axis.     

(Aqua‐2κO)bis(2,2′‐bipyridine‐1κ2N,N′){μ‐N‐[3‐(dimethylamino)propyl]‐N′‐(2‐oxidophenyl)oxamidato(3−)‐1:2κ2O,O′:κ4O′′,N,N′,N′′}copper(II)nickel(II) perchlorate

The title complex, [CuNi(C₁₃H₁₆N₃O₃)(C₁₀H₈N₂)₂(H₂O)]ClO₄, has a cis‐oxamide‐bridged heterobinuclear cation, with a Cu...Ni separation of 5.3297 (6) Å, counterbalanced by a disordered perchlorate anion. The Cu^II and Ni^II cations are located in square‐pyramidal and octahedral coordination environments, respectively. The complex molecules are assembled into a three‐dimensional supramolecular structure through hydrogen bonds and π–π stacking interactions. The influence of the two types of metal cation on the supramolecular structure is discussed.     

catena‐Poly[bis[tetraaquacobalt(II)‐μ‐4,4′‐bipyridine‐κ2N:N′] benzene‐1,2,4,5‐tetracarboxylate(4−) dihydrate]

The title compound, [Co(C₁₀H₈N₂)(H₂O)₄]₂(C₁₀H₂O₈)·2H₂O, consists of two crystallographically independent Co^II atoms linked by 4,4′‐bi­pyridine ligands into one‐dimensional chains, which are further connected into a three‐dimensional framework linked by [C₆H₂(COO)₄]^4? anions and water mol­ecules, achieved through complex hydrogen bonding.     

(1,3‐Dimethylimidazolidine‐2‐selone‐κSe)bis(1,10‐phenanthroline‐κ2N,N′)copper(II) bis(perchlorate) and bis(2,2′‐bipyridyl‐κ2N,N′)(imidazolidine‐2‐thione‐κS)copper(II) bis(perchlorate)

In the first title salt, [Cu(C₁₂H₈N₂)₂(C₅H₁₀N₂Se)](ClO₄)₂, the Cu^II centre occupies a distorted trigonal–bipyramidal environment defined by four N donors from two 1,10‐phenanthroline (phen) ligands and by the Se donor of a 1,3‐dimethylimidazolidine‐2‐selone ligand, with the equatorial plane defined by the Se and by two N donors from different phen ligands and the axial sites occupied by the two remaining N donors, one from each phen ligand. The Cu—N distances span the range 1.980 (10)–2.114 (11) Å and the Cu—Se distance is 2.491 (3) Å. Intermolecular π–π contacts between imidazolidine rings and the central rings of phen ligands generate chains of cations. In the second salt, [Cu(C₁₀H₈N₂)₂(C₃H₆N₂S)](ClO₄)₂, the Cu^II centre occupies a similar distorted trigonal–bipyramidal environment comprising four N donors from two 2,2′‐bipyridyl (bipy) ligands and an S donor from an imidazolidine‐2‐thione ligand. The equatorial plane is defined by the S donor and two N donors from different bipy ligands. The Cu—N distances span the range 1.984 (6)–2.069 (7) Å and the Cu—S distance is 2.366 (3) Å. Intermolecular π–π contacts between imidazolidine and pyridyl rings form chains of cations. A major difference between the two structures is due to the presence in the second complex of two N—H...O hydrogen bonds linking the imidazolidine N—H hydrogen‐bond donors to perchlorate O‐atom acceptors.     

Dichloro(4,4′‐dinonyl‐2,2′‐bipyridine‐κ2N,N′)platinum(II)

The title compound, [PtCl₂(C₂₈H₄₄N₂)], is a new square‐planar Pt^II complex con­taining a bi­pyridine moiety with two long alkyl‐chain substituents. The complex forms a segregated packing structure made up of the alkyl‐chain layers and paired coordination sites.     

The double‐stranded ladder‐like structure of poly[[bis(μ2‐acetato‐κ2O:O′)bis(acetato‐κO)bis(μ‐4,4′‐bipyridine‐κ2N:N′)dicopper(II)] 4‐nitrophenol disolvate tetrahydrate]

The reaction of 4,4′‐bipyridine with copper acetate in the presence of 4‐nitrophenol led to the formation of the title compound, {[Cu(CH₃COO)₂(C₁₀H₈N₂)]·C₆H₅NO₃·2H₂O}_n. The complex forms a double‐stranded ladder‐like coordination polymer extending along the b axis. The double‐stranded polymers are separated by 4‐nitrophenol and water solvent molecules. The two Cu^II centres of the centrosymmetric Cu₂O₂ ladder rungs have square‐pyramidal coordination environments, which are formed by two acetate O atoms and two 4,4′‐bipyridine N atoms in the basal plane and another acetate O atom at the apex. The ladder‐like double strands are separated from each other by one unit‐cell length along the c axis, and are connected by the water and 4‐nitrophenol molecules through a series of O—H...O and C—H...O hydrogen‐bonding interactions and two unique intermolecular π–π interactions.     

catena‐Poly[[(2,2′‐biimidazole‐κ2N,N′)chloro­copper(II)]‐μ‐chloro]

In the polymeric title compound, [CuCl₂(C₆H₆N₄)]_n, each Cu^II ion is five‐coordinated by four basal atoms (two N atoms from a 2,2′‐biimidazole mol­ecule and two Cl⁻ anions) and one axial Cl⁻ anion, in a distorted square‐pyramidal coordination geometry. Cl⁻ anions bridge the {Cu(C₆H₆N₄)Cl} units into one‐dimensional linear chains, which are reinforced by π–π inter­actions. Adjacent linear chains are linked by N—H⋯Cl hydrogen bonds, resulting in a grid layer. The hydrogen‐bonding pattern can be described in graph‐set notation as C(9)R(9)R(14). This study extends our knowledge of the multifunctional properties of the 2,2′‐biimidazole ligand and of the coordination stereochemistry of copper(II).     

[N,N′‐Bis(3‐aminopropyl)ethylenediamine‐κ4N,N′,N′′,N′′′](trithiocyanurato‐κ2N,S)zinc(II) ethanol solvate

In the crystal structure of the title compound, [N,N′‐bis(3‐­amino­propyl)­ethyl­enedi­amine‐κ⁴N,N′,N′′,N′′′][1,3,5‐triazine‐2,4,6(1H,3H,5H)‐tri­thionato(2−)‐κ²N,S]­zinc(II) ethanol sol­vate, [Zn(C₈H₂₂N₄)₂(C₃HN₃S₃)]·C₂H₆O, the Zn^II atom is octa­hedrally coordinated by four N atoms [Zn—N = 2.104 (2)–2.203 (2) Å] of a tetradentate N‐donor N,N′‐bis(3‐­amino­propyl)­ethyl­enedi­amine (bapen) ligand and by two S and N atoms [Zn—S = 2.5700 (7) Å and Zn—N = 2.313 (2) Å] of a tri­thio­cyanurate(2−) (ttcH²⁻) dianion bonded as a bidentate ligand in a cis configuration. The crystal structure of the compound is stabilized by a network of hydrogen bonds.     

Synthesis,crystal structure and magnetic properties of (acetato‐κ2O,O′)bis(5,5′‐dimethyl‐2,2′‐bipyridine‐κ2N,N′)nickel(II) perchlorate monohydrate

The title hydrated ionic complex, [Ni(CH₃COO)(C₁₂H₁₂N₂)₂]ClO₄·H₂O or [Ni(ac)(5,5′‐dmbpy)₂]ClO₄·H₂O (where 5,5′‐dmbpy is 5,5′‐dimethyl‐2,2′‐bipyridine and ac is acetate), (1), was isolated as violet crystals from the aqueous ethanolic nickel acetate–5,5′‐dmbpy–KClO₄ system. Within the complex cation, the Ni^II atom is hexacoordinated by two chelating 5,5′‐dmbpy ligands and one chelating ac ligand. The mean Ni—N and Ni—O bond lengths are 2.0628 (17) and 2.1341 (15) Å, respectively. The water solvent molecule is disordered over two partially occupied positions and links two complex cations and two perchlorate anions into hydrogen‐bonded centrosymmetric dimers, which are further connected by π–π interactions. The magnetic properties of (1) at low temperatures are governed by the action of single‐ion anisotropy, D, which arises from the reduced local symmetry of the cis‐NiO₂N₄ chromophore. The fitting of the variable‐temperature magnetic data (2–300 K) gives g_iso = 2.134 and D/hc = 3.13 cm⁻¹.     

catena‐Poly[[aqua­(2,2′‐bipyridine‐κ2N,N′)cadmium(II)]‐μ‐4‐carboxyl­atophenoxy­acetato‐κ3O:O4,O4′]

In the title compound, [Cd(C₉H₆O₅)(C₁₀H₈N₂)(H₂O)]_n, the Cd^II atom is coordinated in a distorted octa­hedral fashion by two carboxyl­ate groups (one in a monodentate and one in a bidentate fashion) from two 4‐carboxyl­ato­phenoxy­acetate anions, two N atoms from a 2,2′‐bipyridine ligand and one aqua ligand. The structure is a helix with a long pitch of 16.441 (5) Å. A three‐dimensional supra­molecular network is further constructed through π–π stacking and hydrogen‐bonding inter­actions between the helices.     

Bis(μ‐N,N‐dimethyldithiocarbamato‐κ3S,S′:S′)bis[(dimethoxyphenylphosphane‐κP)(N,N‐dimethyldithiocarbamato‐κ2S,S′)cobalt(III)] bis(hexafluorophosphate)

Purple prismatic crystals of the title compound, [Co₂(C₃H₆NS₂)₄(C₈H₁₁O₂P)₂](PF₆)₂, were obtained by repeated recrystallization of trans‐[Co(C₃H₆NS₂)₂‐(C₈H₁₁O₂P)₂]PF₆ from CH₃CN/Et₂O and then from MeOH/CH₂Cl₂; during recrystallization one of the P(OMe)₂Ph ligands was dissociated from the Co^III center and the resulting Co^III complex fragment underwent dimerization. The complex cation has a dinuclear structure bridged by one S atom of each of two of the N,N‐di­methyl­di­thio­carbamate ligands, and has crystallographically imposed C₂ symmetry. Two P(OMe)₂Ph ligands are coordinated at the transoid positions of the Co₂(μ‐C₃H₆NS₂)₂(C₃H₆NS₂)₂ moiety, with Co—P bond lengths of 2.1921 (11) Å.     

(1H‐Pyrazole‐κN2)(2,2′:6′,2′′‐terpyridine‐κ3N,N′,N′′)platinum(II) bis(perchlorate) nitromethane monosolvate

The reaction between [PtCl(terpy)]·2H₂O (terpy is 2,2′:6′,2′′‐terpyridine) and pyrazole in the presence of two equivalents of AgClO₄ in nitromethane yields the title compound, [Pt(C₃H₄N₂)(C₁₅H₁₁N₃)](ClO₄)₂·CH₃NO₂, as a yellow crystalline solid. Single‐crystal X‐ray diffraction shows that the dicationic platinum(II) chelate is square planar with the terpyridine ligand occupying three sites and the pyrazole ligand occupying the fourth. The torsion angle subtended by the pyrazole ring relative to the terpyridine chelate is 62.4 (6)°. Density functional theory calculations at the LANL2DZ/PBE1PBE level of theory show that in vacuo the lowest‐energy conformation has the pyrazole ligand in an orientation perpendicular to the terpyridine ligand (i.e. 90°). Seemingly, the stability gained by the formation of hydrogen bonds between the pyrazole NH group and the perchlorate anion in the solid‐state structure is sufficient for the chelate to adopt a higher‐energy conformation.