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Four coordination compounds, that include the discrete binuclear complex [Zn(H2O)4(bda4Py)]2(SO4)2 (1), two isomorphous one-dimensional coordination polymers, {[Zn(NO3)2(bda4Py)2]·2H2O}n (2) and {[Cd(NO3)2(bda4Py)2]·2H2O}n (3), and one two-dimensional coordination polymer {[Cd(bda4Py)2(dpa)2]·2H2O}n (4) [where bda4Py = N-((pyridin-4-yl)methylene)benzene-1,4-diamine, H2dpa = diphenic acid, as a potential anionic competitor ligand having two carboxylic groups] were obtained as the products of partial hydrolysis of the ligand N1,N4-bis(pyridin-4-ylmethylene)-benzene-1,4-diamine (bda4bPy) in the reaction conditions. Single crystal X-ray data reveal that N-((pyridin-4-yl)methylene)benzene-1,4-diamine acts as a bidentate linker between two metal centers through nitrogen atoms of pyridino- and amino-groups. The additional stabilization of the crystalline solids 1–4 is provided via hydrogen bonds. N-((pyridin-4-yl)methylene)benzene-1,4-diamine (bda4Py) was also obtained by direct synthesis, and two ligands (bda4bPy and bda4Py) were characterized in the solid state and in solution by spectroscopic (FTIR, UV–vis, NMR) methods. Luminescence studies for the reported compounds are also documented.

Eight mixed-ligand coordination networks, [Cd(2-aba)(NO3)(4-bphz)3/2]n&middot, n(dmf) (1), [Cd(2-aba)2(4-bphz)]n&middot, 0.75n(dmf) (2), [Cd(seb)(4-bphz)]n&middot, n(H2O) (3), [Cd(seb)(4-bpmhz)]n&middot, n(H2O) (4), [Cd(hpa)(3-bphz)]n (5), [Zn(1,3-bdc)(3-bpmhz)]n&middot, n(MeOH) (6), [Cd(1,3-bdc)(3-bpmhz)]n &middot, 0.5n(H2O)&middot, 0.5n(EtOH) (7), and [Cd(NO3)2(3-bphz)(bpe)]n&middot, n(3-bphz) (8) were obtained by interplay of cadmium nitrate tetrahydrate or zinc nitrate hexahydrate with 2-aminobenzenecarboxylic acid (H(2-aba)), three dicarboxylic acids, sebacic (decanedioic acid, H2seb), homophthalic (2-(carboxymethyl)benzoic acid, H2hpa), isophthalic (1,3-benzenedicarboxylic acid, H2(1,3-bdc)) acids, bis(4-pyridyl)ethane (bpe) and with four azine ligands, 1,2-bis(pyridin-4-ylmethylene)hydrazine (4-bphz), 1,2-bis(1-(pyridin-4-yl)ethylidene) hydrazine (4-bpmhz), 1,2-bis(pyridin-3-ylmethylene)hydrazine (3-bphz), and 1,2-bis(1-(pyridin-3-yl) ethylidene)hydrazine (3-bpmhz). Compounds 1 and 2 are 1D coordination polymers, while compounds 3&ndash, 8 are 2D coordination polymers. All compounds were characterized by spectroscopic and X-ray diffraction methods of analysis. The solvent uptakes and stabilities to the guest evacuation were studied and compared for 1D and 2D coordination networks. The de-solvated forms revealed a significant increase of emission in comparison with the as-synthesized crystals.

A series of homobi- and polynuclear zinc and cadmium coordination compounds supported by 1,2-cyclohexanedionedioxime and bridging bidentate ligands: 4,4'-bipyridyl, 1,2-bis(4-pyridyl) ethane, 1,3-bis(4-pyridyl) propane and dipiridil sulfide were characterized by the experimental techniques of 1H and 13C NMR spectroscopy. Individual NMR data of compounds are consistent with their assignment as complexes.

A new two dimensional 2,2′-bipyridine-4,4′-dicarboxylate Zn(II) coordination polymer was obtained by hydrothermal synthesis and characterized by IR spectrum and single-crystal X-ray diffraction. The crystal lattice hosts the N,N-dimethylformamide and water solvent molecules. The new material reveals blue-orange luminescence upon excitation with ultraviolet light.

New coordination polymers are reported. All polymers were prepared from a blend of four dicarboxylic acids, three neutral nicotinamide ligands, and Zn(II) or Cd(II) salts. The acids included: malonic (H2mal), succinic (H2suc), adipic (H2adi), and 1,4-benzenedicarboxylic (H2bdc) acids, with all of them varying in length and rigidity of the carbon skeletons. The neutral ligands included two positional isomers, isonicotinamide (iso-nia) and nicotinamide (nia), and a nia thio-analogue, thionicotinamide (S-nia). The preparation resulted in eight Cd(II) and four Zn(II) coordination polymers: [Cd2(suc)(sucH)2(nia)4]n (1), {[Cd(suc)(nia)3]·H2O·dmf}n (2), {[Cd(adi)(iso-nia)2]·dmf}n (3), [Cd(adi)(iso-nia)2]n, (4), {[Zn(mal)(iso-nia)(H2O)]·dmf}n (5), {[Cd(mal)(iso-nia)(H2O)]·dmf}n (6), {[Zn(mal)(nia)(H2O)]·dmf}n (7), {[Cd(mal)(nia)(H2O)]·dmf}n (8), {[Zn(mal)(S-nia)(H2O)]·dmf}n (9), {[Zn(bdc)(nia)2]·dmf}n (10), {[Cd(bdc)(nia)2]·dmf}n (11), and nicotinamide-free {[Cd(bdc)(H2O)2(dmf)]·dmf}n (12). Compounds 1–4 and 12 consist of one-dimensional arrays, while compounds 5–11 are two-dimensional coordination arrays. The coordination cores in 1, 3, 4, 10, and 11 present {M2(COO)2} (M = Zn, Cd) binuclear clusters, while the networks of 2, 5–9 and 12 are built on mononuclear metal nodes with nicotinamide ligands acting as double or single pillars. The structure-confirmed single crystal to single crystal transformation of 3 into 4 was detected and reported. While 1 and 4 are solvent-free apohosts, the remaining solids acted as hosts of water and dmf solvent which are accommodated in the crystal lattices as coordinated ligands or lattice solvents. The new solids were characterized by IR spectroscopy, thermogravimetric analysis, and single-crystal and powder X-ray diffraction methods. The luminescence properties of six as-synthesized coordination polymers and of some activated products are reported. The influence of the metal, ligand, and solvent on tuning the structures and emission properties was monitored, and the most impressive effects were interpreted with the help of TD-DFT computations.

Using the ‘dicarboxylic acid/oxime blend approach’ nine coordination polymers, [M(fum)(2-pyao)2]n, M = Mn(II), Zn(II), Cd(II) (1–3), [Mn(1,3-bdc)(2-pyao)2]n (4), [Cd(1,3-bdc)(2-pyao)]n (5), {[Cd(1,3-bdc)(4-pyao)(H2O)2]·dmf·H2O}n (6), {[Cd(1,4-bdc)(4-pyao)2(H2O)]·dmf}n (7) and {[M(1,4-bdc)(4-pyao)2]·dmf}n, M = Zn(II), Cd(II) (8, 9) (where 2-pyao = pyridine-2-aldoxime, 4-pyao = pyridine-4-aldoxime, fumH2 = fumaric acid, 1,3-bdcH2 = 1,3-benzenedicarboxylic acid and 1,4-bdcH2 = 1,4-benzenedicarboxylic acid) have been prepared, and their crystal structures have been determined by single crystal X-ray diffraction. Compounds 1–4, 6 and 7 represent 1D coordination polymers, while compounds 5, 8 and 9 represent laminar 2D structures. In compounds 1–4 two terminal 2-pyao ligands take the common bidentate chelating coordination mode that results in five-membered chelate rings revealing a “butterfly wings” shape. The oxime’s hydroxyl group participates in an intramolecular OH⋯O hydrogen bond with the dicarboxylic oxygen atoms, which are uncoordinated to the metal center, thus fortifying the metals’ coordination cores. In 6–9 the pillared monodentate 4-pyao ligands, due to their bulkiness and terminal hydroxyl-groups, essentially increase the solvent accessible areas, and the hydrophilic regions in the structures facilitate the accommodation of polar solvents (dmf and water) and their retention in the crystal lattice via hydrogen bonding with OH-ligands (4-pyao, water). All the compounds were tested as luminescent materials, with the Cd-based polymers 3, 5 and 6 revealing the highest emission response.

The reaction of a ditopic ligand, 1,4-benzenedicarboxylic acid (H 2 bdc) with Co(CH 3 COO) 2 ·4H 2 O in solution resulted in a solvent-rich layered coordination polymer with the composition {[Co 2 (μ 2 -OH 2 )(bdc) 2 (dmf) 2 (H 2 O) 2 ]·(dmf)·3(H 2 O)} n ( 1 ) whose crystal structure was determined by single crystal X-ray diffraction. The compound is built on the binuclear {Co 2 (μ 2 -OH 2 )(COO) 2 } metal clusters, where each Co(II) atom is coordinated by six oxygen atoms in a distorted octahedral arrangement. The crystal lattice of 1 hosts the dmf and water solvent molecules via the OH⋯O hydrogen bonding with coordination network. The easy destruction of the crystals due to the partial solvent loss occurs rapidly in ambient conditions and is confirmed by the TGA data.

The combination of [Cu(II)(2,2'-bpy)]2+ and [Cu(II)(phen)]2+ (2,2'-bpy = 2,2'-bipyridine; phen = 1,10-phenanthroline) corner fragments predisposed to pi-pi stacking interactions with bridging ligands 4,4'-bipyridine (4,4'-bpy), 4,4'-bipyridinethane (bpe), and 4,4'-bipyridinepropane (bpp) in the presence of linear SCN-, or tetrahedral ClO4- or BF4- inorganic anions and/or organic acetate anion provides access to a series of new metal-organic materials including non-centrosymmetric polymeric chains, whose architectures were confirmed through single crystal X-ray crystallographic analysis. The nine reported compounds comprise one mononuclear complex, [Cu(2,2'-bpy)2(CH3COO)]-(SCN)(H2O) (1), three binuclear complexes, [Cu2(2,2'-bpy)2(CH3COO)2-(SCN)2(4,4?-bpy)]0.5dmf (2), [Cu2(phen)2(CH3COO)2(SCN)2(bpe)] (3), [Cu2(phen)2(SCN)4(bpe)] (4), and five one-dimensional coordination polymers, {[Cu(2,2'-bpy)(4,4'-bpy)(ClO4)2](H2O)}n (5), {[Cu(phen)(4,4'-bpy)(BF4)2]- (H2O)}n (6), {[Cu(2,2'-bpy)(ClO4)(H2O)(bpp)](ClO4)}n (7), {[Cu(phen)- (ClO4)(dmf)(bpp)](ClO4)}n (8), and {[Cu(phen)(bpp)(BF4)2][Cu(phen)(bpp)2(BF4)](BF4)}n (9). Coordination polymers represent the neutral (5, 6), cationic (7, 8), or a blend of neutral and cationic chains (9), and differ by the Cu(II) coordination cores, conformations of the bridging ligands, and functions of the anions. All compounds except 7 reveal cooperative pi-pi stacking interactions of corner fragments. As expected for the paramagnetic d9 Cu(II) complexes, the polymeric solids show the luminescence quenching. The second order nonlinear optical properties of powders of the non-centrosymmetric compounds 8 and 9 were also tested.

On the way to adsorptive materials with extended metal-dioxime platform three metal–organic compounds were obtained from the systems Zn(II)/Cd(II)−1,2-cyclohexanedionedioxime−bipyridine-like ligand by variation of starting salts and bipyridine ligands, and their structures were confirmed by single crystal X-ray diffraction. The crystalline solids include one-dimensional coordination polymers {[Cd(HCOO)2(nioxH2)(bpp)]·0.25H2O)}n (1), {[Zn(nioxH2)(nioxH)(bpe)]·[F]·dmf}n (2), and mononuclear complex [Cd(nioxH2)3]·[F]2 (3), where nioxH2 = 1,2-cyclohexanedionedioxime; bpe = 1,2-bis(4-pyridyl) ethane; bpp = 1,3-bis(4-pyridyl) propane; dmf = N,N′-dimethylformamide. Compound 2 represents the unique example of 1D cationic coordination polymer with an extended Zn(II) – dioxime/dioximate equatorial platform, and the charge balancing by fluoride anion entrapped in the metal second coordination sphere. Both compounds 2 and 3 with the fluoride entrapping in the metals’ second coordination spheres reveal the luminescence attenuation, and might be further studied as luminescent probes for fluoride anion in the solid state. DFT calculations have been performed to elucidate the nature of studied emissive states involved in luminescence of 1, 2 and 3.

Seven mixed-ligand 1D coordination polymers [Zn2(4-bphz)(2-tpc)4]n (1), [Zn2(4-bpmhz)(2-tpc)4]n (2), [Cd(4-bphz)2(2-tpc)2]n (3), [Zn(3-bphz)(2-tpc)2]n (4), [Zn(3-bpmhz)(2-tpc)2]n (5), [Cd(4-bpmhz)(2-tpc)2]n·0.5n(4-bpmhz) (6), [Cd(3-bpmhz)(2-tpc)2]n·0.5n(H2O) (7) (where 2-tpc = 2-thiophenecarboxylate, 4-bphz = 1,2-bis(pyridin-4-ylmethylene) hydrazine, 4-bpmhz = 1,2-bis(1-(pyridin-4-yl)ethylidene)hydrazine, 3-bphz = 1,2-bis(pyridin-3-ylmethylene)hydrazine, and 3-bpmhz = 1,2-bis(1-(pyridin-3-yl)ethylidene)hydrazine) were prepared and studied using spectroscopic (FTIR, UV–Vis) and X-ray diffraction methods of analysis. Similarly, four bidentate-bridging azine ligands provide the polymers’ extension, while the different mononuclear/binuclear metal nodes demonstrate the variable metals’ coordination capacities that influence the crystal packing motifs and inclusion properties. The guest-free arrays 1–5 pack in parallel stacking modes, while the inclusion compounds 6 and 7 reveal criss-cross packing arrangements with large channels where guest molecules (4-bpmhz/water) serve as structure-directing templates in the formation of crystal structures. The distributions of different types of intermolecular interactions with respect to the percentage of stacking interactions in 1–7 were quantified by Hirshfeld surface and fingerprint plots analysis. The guest-exchange properties for 6 and the solid state emissive properties for 1–7 are reported.

Reactions of zinc and cadmium sulfates with 1,2-bis(pyridin-3-ylmethylene)hydrazine (3-bphz), 1,2-bis(pyridin-4-ylmethylene)hydrazine (4-bphz), and two methylated derivatives, 1,2-bis(1-(pyridin-3-yl)ethylidene)hydrazine (3-bpmhz) and 1,2-bis(1-(pyridin-4-yl)ethylidene)hydrazine (4-bpmhz) resulted in eight coordination compounds. For Zn(II) the structural landscape includes binuclear complexes and two-dimensional coordination polymers, [Zn2(3-bphz)(H2O)10](SO4)2.4H2O (1), [Zn2(SO4)2(3-bphz)(H2O)4]n (2), [Zn2(3-bpmhz)3(H2O)8](SO4)2 (3), and {[Zn(SO4)(4-bpmhz)(H2O)2].1.5(H2O)·0.25(4-bpmhz)}n (4). For Cd(II) two- and three-dimensional coordination networks, {[Cd(SO4)(4-bpmhz)(H2O)1.32]·1.2(H2O)}n (5), [Cd(SO4)(3-bpmhz)(H2O)]n (6), {[Cd(SO4)(4-bphz)(H2O)]·(H2O.C2H5OH)}n (7), and [Cd3(SO4)3(3-bphz)3(H2O)2]n (8) are reported. The extension of crystal structures up to two- and three-dimensional coordination networks has been achieved via bidentate bridging neutral azine ligands, and bi- and tridentate bridging sulfate anions that provide the metal-sulfate inorganic scaffolds in the forms of different one- and two-dimensional coordination arrays. The new crystalline solids were studied by X-ray single crystal and powder diffraction, spectroscopic and thermogravimetric analytical methods. The water-sulfate-anion interplay, similarities and dissimilarities in the coordination networks' topologies, the inherent chiralities of coordination networks, an impact of ligands’ methylation on solvent uptake, and the emission events accompanying the thermal stress are demonstrated and discussed.

Seven new coordination polymers [Zn(I)2(4-bpmhz)]n (1), [Cd(I)2(4-bpmhz)]n (2), [Zn(I)2(3-bpmhz)]n (3), [Cd(I)2(3-bpmhz)2]n (4), [Zn(NO3)2(H2O)2(4-bpmhz)]n·0.5n(EtOH) (5), [Cd(NO3)2(4-bpmhz)3/2(MeOH)]n·0.5nH2O (6) and [Zn(NO3)2(3-bpmhz)2]n (7) were prepared following the reactions of the zinc and cadmium iodide or nitrate salts with the methylated azine ligands of the bis-monodentate N,N′-donor type, 1,2-bis(1-(pyridin-4-yl)ethylidene)hydrazine (4-bpmhz) and 1,2-bis(1-(pyridin-3-yl)ethylidene)hydrazine (3-bpmhz). The single-crystal X-ray diffraction studies show that compounds 1–5, and 7 display 1D chain structures, while compound 6 shows a 2D coordination network, and both 4-bpmhz and 3-bpmhz act as bidentate bridging ligands. The crystals 1 and 2 are isomorphous, and differ by the metal cation only. The single coordination chains in 1–3 have zigzag structures; they are linear in 5, while 4 and 7 display similar double-chain structures. The crystal packing in 5 and 6 provides cavities occupied by solvent molecules, ethanol and water. The compounds were characterized in the solid state and in solution by spectroscopic (FTIR, UV–Vis, NMR) methods; the solid state emissive properties were studied for all compounds, while their thermal stability and behaviour were investigated by thermogravimetry under inert atmosphere, while the thermochromism for several compounds was registered and discussed.

Three binuclear and one mononuclear cobalt(III) dioximates with the compositions [Co2(dmgH)4(bpy)Cl2]·1.5dmf (1), [Co2(nioxH)4(bpy)Cl2]·0.5H2O (2), [Co2(dmgH)4(bpe)Cl2]·0.5H2O (3), and [Co(dmgH)2(bpy)Cl]·H2O (4) (where dmgH2 = dimethylglyoxime, nioxH2 = 1,2-cyclohexanedionedioxime, bpy = 4,4′-bipyridine, bpe = 1,2-bis(4-pyridyl)ethane, and dmf = N,N-dimethylformamide) were prepared by replacement of water molecule in Co(III) mononuclear dioximates by bpy and bpe ligands. All compounds were characterized by single-crystal X-ray diffraction and spectroscopic techniques. In all complexes Co(III) atoms have an identical octahedral N5Cl environment formulated by four nitrogen atoms of two mono-deprotonated oxime ligands in a square planar mode, and the nitrogen atom of the bpy/bpe molecules and chloride atom in the axial positions. In 1–3 bpy/bpe exobidentate spacer ligands serve as bridging “rods” and unite two planar cobalt(III) bis-dioximates in binuclear complex with wheel-and-axle topology. The packing of...

Heating of a pink two-dimensional Co(II) coordination network {[Co2(μ2-OH2)(bdc)2(S-nia)2(H2O)(dmf)]·2(dmf)·(H2O)}n (1) built from 1,4-benzenedicarboxylic acid (H2bdc) residues and thionicotinamide (S-nia) ligands initiates a single-crystal-to-single-crystal transition accompanied by removal of both coordinated and co-crystallized solvents. In the dry blue form, [Co(bdc)(S-nia)]n (dry_1), the Co(II) centers changed from an octahedral to a square pyramidal configuration.

A new three-dimensional coordination polymer, {[Co(μ2-H2O)(bdc)(H2O)(dmf)]·0.5H2O}n (1), was obtained as a by-product in the synthesis of the laminar solid {[Co2(μ2-H2O)(bdc)2(S-nia)2(H2O)(dmf)]·(dmf)2·H2O}n (2) (where H2bdc = 1,4-benzenedicarboxylic acid, S-nia = thionicotinamide, dmf = N,N′-dimethylformamide). The three-dimensional network in 1 is organized of Co(II) atoms in O6 octahedral coordination environments separated by μ2-water molecules in coordination chains. The bdc2− anions coordinate in monodentate mode and also act as bridging ligands that extend the structure in two other directions. The coordination cores of two crystallographically different Co(II) atoms are completed by either two dmf or two water molecules. The rhombohedral open channels contain water molecules. The evacuation of solvents from 1 occurs as a single crystal to single crystal transformation and results in MOF-71, [Co(bdc)(dmf)]n, whose structure was confirmed by single crystal X-ray diffraction.

Six mixed-ligand Co(II) coordination polymers, {[Co(adi)(iso-nia)2]·dmf}n (1), [Co(adi)(iso-nia)2]n (2), {[Co2(suc)(ac)2(iso-nia)4][Co2(suc)(sucH)2(iso-nia)4]·2dmf}n (3), [Co(adi)(nia)2]n (4), {[Co(bdc)(nia)2]·dmf}n (5), and {[Co(mal)(S-nia)(H2O)]·dmf}n (6), were synthesized and characterized by single crystal X-ray analysis. They are based on four dicarboxylic acids, namely, malonic (H2mal), succinic (H2suc), adipic (H2adi), and 1,4-benzenedicarboxylic (H2bdc) acids, as well as three nicotinamide-like ligands, isonicotinamide (iso-nia), nicotinamide (nia) and thionicotinamide (S-nia). Compounds 1, 2, and 3 represent one-dimensional coordination polymers, whereas 4, 5, and 6 exhibit two-dimensional structures. The coordination arrays in 1–5 are built from the similar [Co2(COO)2] binuclear clusters, while framework 6 is based on mononuclear metal nodes. All crystal lattices are supported by hydrogen bonding with nicotinamide-like ligands acting as pillars or dangling terminal ligands. Four crystal lattices...

A one-dimensional linear coordination polymer {[Cu3(μ3-OH)(2-pyao)3(bdc)]·6(H2O)}n () composed of trinuclear [Cu3(μ3-OH)(2-pyao)3](2+) metallacrown cores bridged by bis-carboxylato linkers has been obtained by treatment of copper(ii) fluoride with pyridine-2-aldoxime (2-pyaoH) ligand and benzene-1,4-dicarboxylic acid (H2bdc). Magnetic susceptibility measurements show strong antiferromagnetic interactions between Cu(ii) centers within the trinuclear metallacrown core with J = -430 cm(-1).

International audience; Interaction of zinc or cadmium formate or acetate with 1,2-cyclohexanedionedioxime (NioxH2) and 4,4′-bipyridine (bpy) resulted in similar binuclear coordination compounds of the general formula [M2(NioxH2)2(X)4(H2O)2(bpy)], where M = Cd and X= HCOO− for 1; M = Zn, Cd and X= CH3COO− for 2 and 3, respectively. When the corresponding sulfate salts were used as precursors in the synthesis, a dioxime-containing one-dimensional (1D) coordination polymer with the chemical formula [Cd(NioxH2)(SO4)·(bpy)](NioxH2)·(H2O)3 (4) was obtained with Cd. All compounds were characterized by X-ray diffraction and spectroscopic techniques, and the thermogravimetric data are presented solely for compound 4. The experimental results demonstrate the successful strategy of using “metal oxime” building blocks in order to design new multinuclear complexes. The study has shown that the geometry and size of the corresponding anions together with their coordinating and hydrogen-bonding properties are essential in determining the final structures.