Tetraaqua‐1κO,2κ3O‐(μ‐2,4‐dinitrophenolato‐1κ2O1,O2:2κO1)(2,4‐dinitrophenolato‐1κ2O1,O2)dilithium(I): a dinuclear lithium(I) complex

The title complex, [Li₂(C₆H₃N₂O₅)₂(H₂O)₄], contains two kinds of Li atoms, viz. five‐coordinated and four‐coordinated. The five‐coordinated Li ion has a tetragonal–pyramidal geometry, with a water molecule in the apical position and four O atoms from two 2,4‐dinitrophenolate (2,4‐DNP) ligands in the basal plane. The four‐coordinated Li ion has a tetrahedral geometry, with three water molecules and one phenolate O atom of a 2,4‐DNP ligand. The Li ions are bridged by a phenolate O atom, giving the complex a dinuclear structure. The crystal packing is stabilized by O—H...O hydrogen‐bonding interactions involving the water molecules and nitro O atoms.     

Poly[(μ2‐aqua‐κ2O:O)(μ3‐azido‐κ3N1:N1:N3)(μ2‐isonicotinato‐κ2O:O′)lead(II)]

In the title compound, [Pb(C₆H₄NO₂)(N₃)(H₂O)]_n, the Pb ion is seven‐coordinated by three N atoms from three azide ligands, two O atoms from two isonicotinate (inic) ligands and two O atoms from two coordinated water molecules, forming a distorted monocapped triangular prismatic coordination geometry. Each azide ligand bridges three Pb^II ions in a μ_1,1,3 coordination mode to form a two‐dimensional three‐connected 6³ topology network extending in the bc plane. The carboxylate group of the inic unit and the aqua ligand act as coligands to bridge Pb^II ions. Adjacent two‐dimensional layers are connected by hydrogen‐bonding interactions between the isonicotinate N atom and the water molecule, resulting in an extended three‐dimensional network. The title complex is the first reported coordination polymer involving a p‐block metal, an azide and a carboxylate.     

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 square‐pyramidal copper(II) complex with strong intramolecular hydrogen bonds: diaqua(N,N′‐dimethylformamide‐κO)bis[2‐(diphenylphosphoryl)benzoato‐κO]copper(II)

In the title Cu^II complex, [Cu(C₁₉H₁₄O₃P)₂(C₃H₇NO)(H₂O)₂], the molecule is bisected by a twofold axis relating the two 2‐(diphenylphosphoryl)benzoate (ODPPB) ligands. The asymmetric unit consists of a Cu^II metal centre on the symmetry axis, an ODPPB ligand, one water ligand and one dimethylformamide (DMF) ligand (disordered around the twofold axis). The Cu^II ion has fivefold coordination provided by two carboxylate O atoms from two ODPPB ligands, two O atoms from two coordinated water molecules and another O atom from a (disordered) DMF molecule, giving a CuO₅ square‐pyramidal coordination geometry. The ODPPB ligand adopts a terminal monocoordinated mode with two free O atoms forming two strong intramolecular hydrogen bonds with the coordinated water molecules, which may play a key role in the stability of the molecular structure, as shown by the higher release temperature for the coordinated water molecules than for the coordinated DMF molecule. The optical absorption properties of powder samples of the title compound have also been studied.     

catena‐Poly­[[[aqua(2‐methyl‐4‐oxo‐4H‐pyran‐3‐olato‐κO3,O4)copper(II)]‐μ‐chloro] monohydrate]

In the title complex, {[Cu(C₆H₅O₃)Cl(H₂O)]·H₂O}_n, the Cu^II atom has a deformed square‐pyramidal coordination geometry formed by two O atoms of the maltolate ligand, two bridging Cl atoms and the coordinated water O atom. The Cu atoms are bridged by Cl atoms to form a polymeric chain. The deprotonated hydroxyl and ketone O atoms of the maltolate ligand form a five‐membered chelate ring with the Cu atom. Stacking interactions and hydrogen bonds exist in the crystal.     

Di‐μ‐acesulfamato‐κ3N,O:O;κ3O:N,O‐bis[(acesulfamato‐κ2N,O)bis(3‐methylpyridine)cadmium(II)]

In the structure of the title compound, [Cd₂(C₄H₄NO₄S)₂(C₆H₇N)₂], the dinuclear Cd^II complex is located on a twofold axis with two Cd²⁺ ions bridged by two oxide O atoms. Each Cd²⁺ ion is additionally coordinated in an equatorial plane by two N and three O atoms of the acesulfamate ligands and axially by two N atoms of the 3‐methylpyridine ligands, resulting in a distorted pentagonal bipyramidal coordination. We present here an example of a supramolecular assembly based on hydrogen bonds in a mixed‐ligand metal complex; intermolecular C—H...O hydrogen bonds give rise to R₄⁴(40) rings, which lead to one‐dimensional chains.     

Bis(μ‐5‐carboxybenzene‐1,3‐dicarboxylato‐κ2O1:O3)bis[(2,2′‐bi‐1H‐imidazole‐κ2N3,N3′)zinc]

The title compound, [Zn₂(C₉H₄O₆)₂(C₆H₆N₄)₂], consists of two Zn^II ions, two 5‐carboxybenzene‐1,3‐dicarboxylate (Hbtc²⁻) dianions and two 2,2′‐bi‐1H‐imidazole (bimz) molecules. The Zn^II centre is coordinated by two carboxylate O atoms from two Hbtc²⁻ ligands and by two imidazole N atoms of a bimz ligand, in a distorted tetrahedral coordination geometry. Two neighbouring Zn^II ions are bridged by a pair of Hbtc²⁻ ligands, forming a discrete binuclear [Zn₂(Hbtc)₂(bimz)₂] structure lying across an inversion centre. Hydrogen bonds between carboxyl H atoms and carboxylate O atoms and between imidazole H atoms and carboxylate O atoms link the binuclear units. These binuclear units are further extended into a three‐dimensional supramolecular structure through extensive O—H...O and N—H...O hydrogen bonds. Moreover, the three‐dimensional nature of the crystal packing is reinforced by the π–π stacking. The title compound exhibits photoluminescence in the solid state, with an emission maximum at 415 nm.     

Acetato(N‐phenylpyridine‐2‐carboxamidato‐κ2N,N)(N‐phenylpyridine‐2‐carboxamide‐κ2N1,O)copper(II)

The title complex, [Cu(C₁₂H₉N₂O)(C₂H₃O₂)(C₁₂H₁₀N₂O)], is a neutral Cu^II complex with a primary N₃O₂ coordination sphere. The Cu centre coordinates to both a deprotonated and a neutral molecule of N‐phenylpyridine‐2‐carboxamide and also to an acetate anion. The coordination around the metal centre is asymmetric, the deprotonated ligand providing two N donor atoms [Cu—N = 1.995 (2) and 2.013 (2) Å] and the neutral ligand providing one N and one O donor atom to the coordination environment [Cu—N = 2.042 (2) Å and Cu—O = 2.2557 (19) Å], the fifth donor being an O atom of the acetate ion [Cu—O = 1.9534 (19) Å]. The remaining O atom from the acetate ion can be considered as a weak donor atom [Cu—O = 2.789 (2) Å], conferring to the Cu complex an asymmetric octahedral geometry. The crystal structure is stabilized by intermolecular N—H...O, C—H...O and C—H...π interactions.     

Poly[[diaqua(N,N‐dimethylformamide‐κO)manganese(II)]‐μ3‐sulfato]

In the title complex, [Mn(SO₄)(C₃H₇NO)(H₂O)₂]_n, each Mn^II ion has a distorted octahedral geometry formed by three O atoms of three different sulfate groups, one O atom of a dimethylformamide ligand and two water molecules. The sulfate groups act as tridentate bridging ligands connecting the Mn^II ions into a two‐dimensional layer structure which can be regraded as a 4.8² network.     

A vanadyl Schiff base complex: {2,2′‐[1,1′‐(o‐phenylenedinitrilo)bis(ethan‐1‐yl‐1‐ylidene)]diphenolato}oxovanadium(IV)

The green crystals of the title compound, [V(C₂₂H₁₈N₂O₂)O], represent a mononuclear oxovanadium complex. The central V^IV centre has a distorted square‐pyramidal coordination. Two N atoms and two O atoms of the Schiff base ligand define the base of the pyramid, and the oxide O atom is in the apical position. Density functional theory (DFT) calculations were performed to analyse the changes in the geometry of the ligand during the complex formation. The most significant changes are observed in the values of the torsion angles in the vicinity of the donor N atoms. The HOMA index (Harmonic Oscillator Model of Aromaticity) has been calculated to compare the aromaticity of the benzene rings in the complex and its ligand.     

Bis(acesulfamato‐κ2N3,O4)bis­(2‐amino­pyrimidine‐κN1)copper(II)

In the crystal structure of the title compound, bis­(2‐amino­pyrimidine‐κN¹)bis­[6‐meth­yl‐1,2,3‐oxathia­zin‐4(3H)‐one 2,2‐dioxide(1−)‐κ²N³,O⁴]copper(II), [Cu(C₄H₄NO₄S)₂(C₄H₅N₃)₂], the first mixed‐ligand complex of acesulfame, the Cu^II centre resides on a centre of symmetry and has an octa­hedral geometry that is distorted both by the presence of four‐membered chelate rings and by the Jahn–Teller effect. The equatorial plane is formed by the N atoms of two amino­pyrimidine (ampym) ligands and by the weakly basic carbonyl O atoms of the acesulfamate ligands, while the more basic deprotonated N atoms of these ligands are in the elongated axial positions with a strong misdirected valence. The crystal is stabilized by pyrimidine ring stacking and by inter­molecular hydrogen bonding involving the NH₂ moiety of the ampym ligand and the carbon­yl O atom of the acesulfamate moiety.     

Poly[[tetraaquabis(μ2‐2‐nitroterephthalato‐κ3O1:O4,O4′)(μ2‐piperazine‐κ3N:N′)dicadmium(II)] dihydrate]

In the title complex, {[Cd₂(C₈H₃NO₆)₂(C₄H₁₀N₂)(H₂O)₄]·2H₂O}_n, the Cd^II atoms show distorted octahedral coordination. The two carboxylate groups of the dianionic 2‐nitroterephthalate ligand adopt monodentate and 1,2‐bridging modes. The piperazine molecule is in a chair conformation and lies on a crystallographic inversion centre. The Cd^II atoms are connected via three O atoms from two carboxylate groups and two N atoms from piperazine molecules to form a two‐dimensional macro‐ring layer structure. These layers are further aggregated to form a three‐dimensional structure via rich intra‐ and interlayer hydrogen‐bonding networks. This study illustrates that, by using the labile Cd^II salt and a combination of 2‐nitroterephthalate and piperazine as ligands, it is possible to generate interesting metal–organic frameworks with rich intra‐ and interlayer O—H...O hydrogen‐bonding networks.     

(N‐{[4‐(1,3‐Benzothiazol‐2‐yl)anilino]carbonylmethyl‐κO}iminodiacetato‐κ3O,N,O′)(1,10‐phenanthroline‐κ2N,N′)cobalt(II) pentahydrate

The title compound, [Co(C₁₉H₁₅N₃O₅S)(C₁₂H₈N₂)]·5H₂O, has a moderately distorted octahedral coordination environment composed of two N atoms of a 1,10‐phenanthroline ligand and one N and three O atoms of an N‐{[4‐(1,3‐benzothiazol‐2‐yl)anilino]carbonylmethyl}iminodiacetate (ZL‐5²⁻) ligand. The ring systems of the phenanthroline and ZL‐5²⁻ ligands are coplanar and the complexes pack in layers parallel to the ab plane with the rings of adjacent complexes facing one another. The layers stack along the c axis and are linked by hydrogen bonds involving the five water solvent molecules in the asymmetric unit and O atoms of the acetate groups of the ZL‐5²⁻ ligand. This is believed to be the first crystal structure of a complex of a 2‐(4‐aminophenyl)benzothiazole ligand.     

mer‐Di­aqua­bis(1H‐imidazole‐κN3)(orotato‐κ2N3,O4)­nickel(II)

The title mononuclear complex, [Ni(C₅H₂N₂O₄)(C₃H₄N₂)₂(H₂O)₂] or [Ni(HOr)(im)₂(H₂O)₂] (im is imidazole and H₃Or is orotic acid, or 2,6‐dioxo‐1,2,3,6‐tetra­hydro­pyrimidine‐4‐carboxylic acid), has been synthesized and the crystal structure determination is reported. The Ni^II ion in the complex has a distorted octahedral coordination geometry comprised of one deprotonated pyrimidine N atom and the adjacent carboxyl­ate O atom of the orotate ligand, two tertiary imidazole N atoms and two aqua ligands. An extensive three‐dimensional network of OW—H⋯O and N—H⋯O hydrogen bonds, and π–π and π–ring interactions are responsible for crystal stabilization.     

(2‐Aminopyrimidine‐κN1)aqua(pyridine‐2,6‐dicarboxylato‐κ3O2,N,O6)copper(II): X‐ray and DFT calculated structure

In the title compound, [Cu(C₇H₃N₂O₄)(C₄H₅N₂)(H₂O)], (I), pyridine‐2,6‐dicarboxylate (pydc²⁻), 2‐aminopyrimidine and aqua ligands coordinate the Cu^II centre through two N atoms, two carboxylate O atoms and one water O atom, respectively, to give a nominally distorted square‐pyramidal coordination geometry, a common arrangement for copper complexes containing the pydc²⁻ ligand. Because of the presence of Cu...X_bridged contacts (X = N or O) between adjacent molecules in the crystal structures of (I) and three analogous previously reported compounds, and the corresponding uncertainty about the effective coordination number of the Cu^II centre, density functional theory (DFT) calculations were used to elucidate the degree of covalency in these contacts. The calculated Wiberg and Mayer bond‐order indices reveal that the Cu...O contact can be considered as a coordination bond, whereas the amine group forming a Cu...N contact is not an effective participant in the coordination environment.     

(2,2′‐Bipyridyl‐κ2N,N′)­bis­(salicyl­ato‐κ2O,O′)­zinc(II)

The asymmetric unit of the title compound, [Zn(C₇H₅O₃)₂(C₁₀H₈N₂)], contains one monomeric zinc complex. The Zn atom is coordinated to one 2,2′‐bipyridyl ligand via both N atoms and to two salicyl­ate anions (Hsal⁻) in a bidentate chelating manner involving carboxyl­ate O‐atom coordination. The complex exhibits a distorted octahedral geometry about the Zn^II atom, with the `apical' positions occupied by one of the two N atoms of the bipyridyl ligand and an O atom from one Hsal<sup>−</sup> ligand; the Zn atom is 0.168 (1) Å out of the `basal' plane. Two intramolecular six‐membered hydrogen‐bonded rings are present, generated from interactions between the carboxyl and hydroxyl groups of the salicyl­ate ligands. The crystal packing is governed by weak C—H⋯O and C—H⋯π interactions.     

Bis(isoquinoline‐1‐carboxylato‐κ2O,N)(1,10‐phenanthroline‐κ2N,N′)zinc(II) dimethylformamide sesqui­solvate

The asymmetric unit of the title compound, [Zn(C₁₀H₆NO₂)₂(C₁₂H₈N₂)]·1.5C₃H₇NO, contains one monomeric zinc com­plex and 1.5 disordered di­methyl­form­amide solvate mol­ecules. The Zn atom is coordinated to one 1,10‐phenanthroline ligand and to two iso­quinoline­carboxyl­ate anions (IQC^?) via their N and O atoms. The complex exhibits a distorted octahedral geometry around the Zn^II atom, with the apical positions occupied by the O atoms of the IQC^? ligands. The Zn atom lies 0.049 (1) Å out of the basal plane. The crystal packing is characterized by several hydrogen bonds.     

Aqua[bis(pyrimidin‐2‐yl‐κN)amine](carbonato‐κ2O,O′)copper(II) dihydrate

The title mononuclear complex, [Cu(CO₃)(C₈H₇N₅)(H₂O)]·2H₂O, was obtained by fixation of CO₂ by a mixture of copper(II) tetra­fluoro­borate and the ligand bis­(pyrimidin‐2‐yl)­amine in ethanol/water. The Cu^II ion of the complex has a distorted square‐pyramidal environment, with a basal plane formed by two N atoms of the ligand and two chelating O atoms of the carbonate group, while the apical position is occupied by the O atom of the coordinating water mol­ecule. In the solid state, hydrogen‐bonding interactions are dominant, the most unusual being the Watson–Crick‐type coplanar ligand pairing through two N—H?N bonds. Lattice water mol­ecules also participate in hydrogen bonding.     

A novel one‐dimensional complex: catena‐poly­[[manganese(III)‐di‐μ‐2‐[(2‐hydroxy­ethyl)­imino­methyl]­phenolato‐κ2O1,N:κO2;κO2:κ2O1] chloride]

In the title one‐dimensional complex, {[Mn^III(C₉H₁₀NO₂)₂]Cl}_n, the Schiff base ligand 2‐[(2‐hydroxy­ethyl)­imino­methyl]­phenolate (Hsae⁻) functions as both a bridging and a chelating ligand. The Mn^III ion is six‐coordinated by two N and four O atoms from four different Hsae⁻ ligands, yielding a distorted MnO₄N₂ octahedral environment. Each [Mn^III(Hsae)₂]⁺ cationic unit has the Mn atom on an inversion centre and each [Mn^III(Hsae)₂]⁺ cation lies about another inversion centre. The chain‐like complex is further extended into a three‐dimensional network structure through Cl⋯H—O hydrogen bonds and C—H⋯π contacts involving the Hsae⁻ rings.     

Bis(1,10‐phenanthroline‐κ2N,N′)(squarato‐κO)copper(II) trihydrate

The title mononuclear [Cu(sq)(phen)₂]·3H₂O complex [sq is squarate (C₄O₄) and phen is 1,10‐phenanthroline (C₁₂H₈N₂)] has been synthesized and the structure consists of a neutral mononuclear [Cu(sq)(phen)₂] unit and three solvate water mol­ecules. The Cu^II ion has distorted square‐pyramidal coordination geometry, comprised of one carboxyl­ate O atom from a monodentate squarate ligand and four N atoms from two chelating phen ligands. An extensive three‐dimensional network of OW—H⋯O/OW hydrogen bonds, face‐to‐face π–­π interactions between the 1,10‐phenanthroline aromatic rings and a weak π–ring interaction are responsible for crystal stabilization.