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The possibility to tune the metal–metal separations in a series of ten Cu(ii) 1D and 2D coordination polymers obtained from pyridine-n-oxime–dicarboxylic acid blends was followed and discussed.

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.

Four Cu(II)-based neutral coordination polymers, 1D {[Cu(isonia)2(adi)(dmf)].0.5H2adi}n (1), 2D {[Cu(isonia)2(adi)](H2O.H2adi)}n (2), 1D {[Cu(pic)(CH3COO)(bpe)].H2O}n (3), and 2D [Cu2(pic)2(CH3COO)2(bpy)]n (4) with biocompatible molecules: isonicotinamide (isonia), pyridine-2-carboxylic (picolinic, Hpic) and adipic (H2adi) acids and 1,2-bis(4-pyridyl)-ethane (bpe) and 4,4′-bipyridine (bpy) as neutral linkers are reported. The polymer extension in 1 and 2 is reached via bidentate bridging adi anions with isonia ligands as single (1) and double (2) pillars. 1D and 2D coordination arrays are associated in elegant 3D H-bonded networks via interplay of robust amide(isonia)…amide(isonia) homosynthon and NH…O(COO–) side interactions. In 3 the pic residue coordinates in a chelate mode and forms the five-membered [Cu(pic)] corner fragment. The structure expansion occurs via bidentate-bridging bpe neutral linker registered in a coordination wire as different conformers thus providing long (Cu-bpe)6 crystallographically unique chain fragment. Oppositely, in 4 the pic residue acts in a bidentate chelate bridging mode and gives rise to the 2D coordination array. The bpy trapping between each two Cu(II) atoms, does not participate in further structure extension. The decisive impact of amido-group of isonia ligand in structure rigidification and retention of protic H2adi and water guest molecules is demonstrated. The gradual decrease of guest’s capacity correlates with an increased liphophilicity of 3 and 4 comparing with 1 and 2.

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.

Dinucleartetracarboxylato-bridged copper(II)solvato-morph [Cu2(OAc)4(ina)2] •2dmso was prepared and studied by IR spectroscopy, TGA analysis and single crystal X-ray method. Cu(II) ions are bridged by four syn,syn-η1:η1:μ carboxylates, showing a paddle-wheel cage-type with a square-pyramidal geometry.

The mechanical features of catena-{(μ2-adipato-O,O′)-bis(pyridine-4-aldoxime)-copper(II)} (1) were studied by the nanoindentation technique under different loads. The newly synthesised metal–organic material 1, with a one-dimensional coordination backbone, revealed plastic deformation evidenced by the sliding steps and nanoindentation load–displacement curves and the lack of cracks inside the indentations and in its neighborhood at all load tests. The pattern of the material movement in the crystal volume and its transfer to the surface associated with the shear-induced breakage of weak interlayer forces and the breakage of hydrogen bonds within the H-bonded layer is suggested.

Three mixed-ligand Cu(II) complexes with compositions [Cu(phen)2(SO4)]·CH3OH (1), [Cu(phen)2(SO4)](H2O)2(dmf) (2), and [Cu(phen)2H2O](SO4)(H2O)4 (3), where phen = 1,10-phenanthroline and dmf = N,N′-dimethylformamide, were prepared and studied. These compounds belong to the landscape of the mononuclear Cu(phen)2 sulfates, and the solvated complexes undergo frequent anion/water exchange at the metal center in aqueous solutions. Complexes are similar by the metal trigonal bipyramidal coordination geometry but differ by the mode of enclathration and number of protic and aprotic solvent guest molecules being accommodated in the crystal lattice. Crystal packing in 1–3 is determined by the robust supramolecular patterns that consist of stacking interactions between the planar extended phen fragments. These are observed in all three solids regardless of the interplay of other noncovalent interactions, including rather strong hydrogen bonds. The dual luminescence is detected at 580 and 470 nm for both crystals of ...

Ten Zn(II) and Cd(II) metal–organic materials were synthesized and studied by the X-ray method. Among these 10 structures, two represent binuclear clusters, and two are one-dimensional (1D) coordination polymers, while five are laminar two-dimensional (2D) solids and one is the three-dimensional (3D) framework. The investigation has been aimed at rational design of coordination polymers decorated by oxime ligands to increase the accessible adsorption area in these newly synthesized solids. The ligands used include three aliphatic dicarboxylic acids, HOOC-(CH2)n-COOH [n = 1, 2, 4 corresponding to malonic (H2mal), succinic (H2suc), and adipic (H2adi) acids], and three neutral oxime ligands [pyridine-2-aldoxime (2-pyao), pyridine-4-aldoxime (4-pyao), and 1,2-cyclohexanedionedioxime (Niox)]. These novel hybrid solids with the compositions [Zn2(suc)2(2-pyao)4]·2H2O 1, [Cd2(suc)(2-pyao)4(H2O)2][BF4]2 2, [Cd(suc)(2-pyao)2]n 3, [Zn(mal)(4-pyao)(H2O)]n 4, [Cd(mal)(4-pyao)(H2O)]n 5, [Zn(suc)(4-pyao)]n 6, [Zn(adi)(4...

Five new coordination polymers, {[Co(OAc)2(bpe)(H2O)]·0.5(dmf)}n (1), {[Co(bpy)2(H2O)4][Co(tfa)(bpy)2(H2O)3](tfa)3·1.5(bpy)}n (2), [Co(tfa)2(dps)4]n (3), {[Co(tfa)2(bpe)4]·H2O}n (4), and [Co(tfa)2(bpp)4]n (5) (where AcO– = CH3CO2–; tfa– = CF3CO2–; bpy = 4,4′-bipyridine; bpe = 1,2-bis(4-pyridyl)ethane; bpp = 1,3-bis(4-pyridyl)propane; dps = 4,4′-dipyridyl sulfide; dmf = N,N′-dimethylformamide) were synthesized by the reactions of Co(OAc)2·4H2O and Co(tfa)2·4H2O with different dipyridyl ligands and characterized by elemental analysis, IR spectra, and X-ray single-crystal diffraction. Compound 1 exhibits extended two-dimensional (2D) networks through the bridging AcO– and bpe ligands. The polymeric motifs in 2–5 are exclusively based on bipyridine-type ligands and results in 1D cationic chains in 2, similar charge-neutral double tapes in 3 and 4, and a 2D polymeric network in 5. In 2–5, the tfa anions coordinate to the Co(II) center in a monodentate mode. An impact of the anion’s fluorination on coordination...

Interaction of zinc(II) and cadmium(II) sulfates with pyridine-4-aldoxime (4-pyao) and pyridine-4-amidoxime (4-pyamo) ligands resulted in four 1D metal–organic materials (MOMs) with identical composition, [M(SO4)A2(H2O)2]n, where M = Zn(II), A = 4-pyao for 1, M = Cd(II), A = 4-pyao for 2, M = Zn(II), A = 4-pyamo for 3, M = Cd(II), A = 4-pyamo for 4, and mononuclear [Zn(SO4)(4-pyamo)2(H2O)3] 5. New coordination polymers represent the mixed-ligand supramolecular isomers different by the twisting of two pyridine-4-oxime ligands in the metal coordination environments, and crystallizing in the different space groups. Conformational preferences and nonlinear optical properties of the 4-pyao and 4-pyamo complexes were investigated using density functional theory. Spectral properties of 1–3 have been also evaluated. The solid-state emission of 1D polymers 1–3 appears to be ligand-based, as the positions of the emission maxima remain practically unchanged from free ligand to complexes. The enhancement of luminesce...

New organic ligand L (1) resulting from isonicotinic hydrazide and 2,4-pentanedione has been prepared and investigated by physicochemical methods, including elemental analysis, 1H and 13C NMR, IR spectroscopy and X-ray studies. The X-ray investigation revealed that the condensation of 2,4-pentanedione with isonicotinic hydrazide is accompanied by the formation of a five-membered ring including three carbon atoms of 2,4-pentanedione and two nitrogen atoms of the isonicotinic hydrazide fragment. The reaction between [Co(DfgH)2Br(H2O)] (DfgH2 = diphenylglyoxime) and L resulted in the formation of the mononuclear octahedral complex [Co(DfgH)2BrL] (2) with the substitution of the water molecule in the apical position by the ligand L. The reaction starting from [Co(DmgH)2Cl(H2O)] (DmgH = dimethylglyoxime) and L resulted in the mononuclear octahedral Co(III) complex with the composition [Co(DmgH)2ClL′] (3), where L′ unexpectedly represents a dehydrated derivative of L. The two coordination compounds are characterized by X-ray diffraction method. The IR, 1H NMR spectral studies of new compounds are also reported.

The syntheses, spectroscopic characterization and crystal structures for eight coordination compounds [Cd(HCO2)2(pya)2] (1), {[M(bdc)(pya)].1.5DMF}n (M = Mn(II), Zn(II), Cd(II) (2–4), [Zn(SO4)(pya)(H2O)3](H2O) (5), [(ZnSO4)2(pya)4] DMF.2H2O (6), [Zn(SO4)(pya)(H2O)2]n (7), and [Cd(SO4)(pya)(H2O)]n (8) [pya = pyridine-2-aldoxime, bdc = 1,4-benzenedicarboxylate, DMF = N,N′-dimethylformamide] are reported. Compounds 1–4 and 6 contain two, while 5, 7, and 8 contain one neutral pya ligand coordinated in a chelate mode to the metal center through the Npyridyl and Noxime atoms. The dicarboxylic bdc anions provide an access to 1D polymeric arrays in 2–4. The hybrid sulfates including discrete mononuclear (5), binuclear (6), and 1D polymeric (7, 8) coordination arrays were obtained due to different binding modes of coordinated sulfate anion. While solid state fluorescence of new polymeric compounds 2–4 is similar to that of the H2bdc ligand, a rare dual emission is observed for compounds 7 and 8. According to TD-DFT calculations, emission at 400 and 650 nm originates from nπ∗ and ππ∗ states of the pya ligand respectively.

Three mononuclear mixed-ligand Cd(II) and Zn(II) dioximes with the compositions [Cd(HCOO) 2 (NioxH 2 ) 2 ] ( 1 ), [Cd(CH 3 COO) 2 (NioxH 2 )(Im) 2 ]·H 2 O ( 2 ) and [Zn(SO 4 )(NioxH 2 ) 2 (H 2 O)]·DMF·2H 2 O ( 3 ), and the Zn(II) dioximate [Zn(NioxH) 2 (An) 2 ]·4H 2 O ( 4 ) (where NioxH 2 = 1,2-cyclohexanedionedioxime, Im = imidazole, An = aniline, DMF = N , N ′-dimethylformamide) were prepared and their structures were determined by single-crystal X-ray crystallography. The structural determination revealed that the coordination geometry around the Cd/Zn centers is distorted octahedral in each complex. In the molecular units 1 , 2 and 3 , the metal atoms have N 4 O 2 environments, while in complex 4 , the Zn(II) cation has an N 6 coordination core. The impact of different ligands on the stereochemistry of the metal center is elucidated. The hydrogen bonds, being the driving forces in the generated self-association patterns, are discussed.

Directed synthesis of dianiline- (DAnH2) and disulfanilamideglyoximes (DSamH2) has been accomplished by condensation of dichloroglyoxime with aniline or sulfanilamide in 1:2 molar ratio, as well as their corresponding Co(III), Ni(II) and Cu(II) coordinative compounds. Composition, structure and some properties of dioximes and complexes have been established by using elemental analysis, UV-Vis, IR and NMRspectroscopies. Dioxime coordination at the central atom and structure of complexes depends on pH of reaction medium: at pH=5-6 - bis-dioximates, whilst at pH=2 – tris-dioximines are obtained.

The reaction of copper(II) acetate or fluoride with classic dioximes in the presence of 1,2-bis(4-pyridyl)ethane resulted in four novel compounds with the compositions [Cu2(dmgH)4bpe] (1), [Cu2(NioxH)4bpe] (2), [Cu2(dpgH)4bpe] (3), and [Cu2(dpgH)4bpe][Cu(dpgH)2bpe]2·2DMF (4) (where dmgH2 = dimethylglyoxime, NioxH2 = 1,2-cyclohexanedionedioxime, dpgH2 = diphenylglyoxime, bpe = 1,2-bis(4-pyridyl)ethane, and DMF = N,N′-dimethylformamide), whose crystal structures were determined by single crystal X-ray diffraction. In the binuclear molecules 1–3, as well as in both binuclear and mononuclear molecules in 4 each Cu(II) atom has an identical N5-environment formulated by four oximic nitrogen atoms of two monodeprotonated ligands in a slightly distorted square planar mode, and the nitrogen atom of the bpe molecule being in the apical position. The new compounds were characterized by elemental analysis, IR spectroscopy and single-crystal X-ray diffraction. Luminescence investigations for 1, 2 and 4 were carried out to clarify whether the guest inclusion in the crystal lattice is accompanied by changes in the emission spectra.

The luminescent heterometallic material, [Na2Zn2{(4-py)C(H)NOH}2(CH3COO)6(H2O)4].2H2O (1), where (4-py)C(H)NOH = pyridine-4-carbaldehyde oxime, was synthesized and characterized by single crystal X-ray method. In the centrosymmetric tetranuclear molecule each sodium site is bound to six oxygen atoms, the donor atoms come from three acetate anions and three water molecules, two of which act as μ2-aqua bridges between Na(I) centers. Each zinc site is bound to three oxygen atoms from the same acetate anions and one nitrogen atom from the capped (4-py)C(H)NOH molecule which coordinates via pyridine nitrogen. The bridging acetate ligands show two coordination modes within one compound.

The interaction of zinc(II) or cadmium(II) sulfate with 4,4′-bipyridine (bpy) or 4,4′-bipyridinethane (bpe) in the presence of 1,2-cyclohexanedionedioxime (NioxH2) resulted in four novel polymeric compounds with the compositions {[Zn(H2O)6][Zn(SO4)2(H2O)2(bpy)][Zn(SO4)(H2O)3(bpy)]}∞ (1), {[Zn(SO4)(NioxH2)(bpy)]·0.5H2O·DMF}∞ (DMF = N,N-dimethylformamide) (2), [Zn(SO4)(NioxH2)(bpe)]∞ (3), and [Cd(SO4)(NioxH2)(bpe)]∞ (4). Compounds were characterized by spectroscopic techniques and single crystal X-ray method. The chiral layer coordination polymer is the robust structural motif in 2–4. Although compounds 3 and 4 were isolated in the same crystallization conditions, the layers of opposite chirality constitute the achiral (3), and the layers of the same chirality result in chiral (4) architectures. All materials display blue luminescence upon excitation with ultraviolet light.

Multicomponent mixed metal ionic-type dioximates, [Со(DH)2(Thio)2][Rh(Thio)6][BF4]4 (1), [Со(DH)2(Thio)2][Rh(Thio)6][TiF6]2·H2O (2) and [Со(NioxH)2(Thio)2]2[Rh(Thio)5Cl][TiF6]2·CH3OH·3H2O (3), where DH2 is dimethylglyoxime, NioxH2 is 1.2-cyclohexanedionedioxime, and Thio is thiourea, were synthesized and their structures were determined by an X-ray method. Compounds 1–3 consist of two different mononuclear coordination cations with cobalt(III) and rhodium(III) as octahedrally coordinated metal centers and fluorine-containing anions as counterions. In the studied systems, Rh(III) mostly binds Thio ligands instead of dioximes, while a typical bis-dioximate in trans geometry is formed by Co(III) with two Thio ligands placed in axial positions. A structural characterization of coordination cations [Rh(Thio)6]3+ and [Rh(Thio)5Cl]2+ is given for the first time. The interactions and arrangement of the components in crystals 1–3 are discussed.

Interaction of cadmium(II) or zinc(II) acetate with 1,2-bis(4-pyridyl)ethane (bpe) in the presence of dioxime(1,2-cyclohexanedionedioxime = NioxH 2 or diphenylglyoxime = dpgH 2 ) resulted in three complexes with the compositions [Cd 2 (CH 3 COO) 4 (NioxH 2 ) 2 (bpe)(H 2 O) 2 ] ( 1 ), [Cd(CH 3 COO) 2 (bpe)(H 2 O)] n ( 2 ) and [Zn(CH 3 COO) 2 (NioxH 2 )(bpe)(H 2 O)] n ( 3 ), which were characterized by single-crystal X-ray diffraction, elemental analysis, IR, and luminescence spectroscopy. Dioxime-containing binuclear molecule 1 and 1D linear polymer 3 possess moderate luminescence properties, while the dioxime-free 1D polymer 2 demonstrates strong blue luminescence.

Two novel Cu(II) dimethylglyoximato complexes of the compositions [Cu 2 (Hdmg) 4 · (γ,γ′-dpy)] 2 · 4H 2 dmg ( 1 ) and [Cu 2 (Hdmg) 4 · (γ,γ′-dpy)] · [Cu(Hdmg) 2 · (γ,γ′-dpy)] · (γ,γ′-dpy) . 2H 2 dmg ( 2 ) (H 2 dmg = dimethylglyoxime, γ,γ′-dpy = γ,γ′-dipyridine) were synthesized and their crystal structures were determined by single-crystal X-ray diffraction. The structure of 1 consists of the neutral [Cu 2 (Hdmg) 4 · (γ,γ′-dpy)] binuclear units and non-coordinated H 2 dmg molecules. The structure of 2 consists of neutral [Cu 2 (Hdmg) 4 · (γ,γ′-dpy)] binuclear and [Cu(Hdmg) 2 · (γ,γ′-dpy)] mononuclear units and non-coordinated H 2 dmg and γ,γ′-dpy molecules. Both in copper(II) dimers and monomers the environment around copper atoms is distorted square pyramidal with four oximate nitrogen atoms building the equatorial plane. A nitrogen atom from γ,γ′-dpy molecule occupies the apical position of the square pyramids around Cu. The Cu(1)⋯Cu(2) separation in the dimers are 11.465(1), 11.431(1) A in 1 and 11.472(2) A in 2 . In both 1 and 2 the neutral species are packed in such a way as to maximize the hydrogen bonding and π–π stacking interactions between the crystal components.

It was elaborated the methodology of synthesizing a series of new dioximates of Co(III) with the general formula [Co(DioxH)2(L)2]X⋅nH2O, where DioxH – the dioxime anione: dimethylglyoxime (DH2), 1,2-cyclohexanedionedioxime (NioxH2); L - thiocarbamide (Thio), pyridine (Py), aniline (An), sulphanilamide (Sam);X - [BF4]-, [ZrF6]2-, [TiF6]2-, whose structures have been studied with the help of contemporary physical methods: spectroscopy IR, UV-Vis, RMN 1H, 19F, X-ray analysis. There were elaborated optimal conditions of using cobalt dioximates with fluorine in order to intensify the biosynthesis of amylases and lipases by Aspergillus and Rhizopus strains, respectively. The tested compounds increase the lipolytic activity of Rhizopus arrhisus micromycetes.

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).

Two new mononuclear coordination compounds, bis{4-[(hydroxyimino)methyl]pyridinium} diaquabis(pyridine-2,5-dicarboxylato-κ2N,O2)zincate(II), (C6H7N2O)2[Zn(C7H3NO4)2(H2O)2], (1), and (pyridine-2,6-dicarboxylato-κ3O2,N,O6)bis[N-(pyridin-4-ylmethylidene-κN)hydroxylamine]zinc(II), [Zn(C7H3NO4)(C6H6N2O)2], (2), have been synthesized and characterized by single-crystal X-ray diffractometry. The centrosymmetric ZnIIcation in (1) is octahedrally coordinated by two chelating pyridine-2,5-dicarboxylate ligands and by two water molecules in a distorted octahedral geometry. In (2), the ZnIIcation is coordinated by a tridentate pyridine-2,6-dicarboxylate dianion and by twoN-(pyridin-4-ylmethylidene)hydroxylamine molecules in a distortedC2-symmetric trigonal bipyramidal coordination geometry.

In the title compound, [Zn(C6H4NO2)2(H2O)2]·0.5C3H7NO, the Zn(II) ion is coordinated in a distorted octa-hedral N2O4 environment by two N,O-chelating pyridine-2-carboxyl-ate ligands and two cis water mol-ecules. The chelating pyridine-2-carboxyl-ate ligands create two five-membered Zn/N/C/C/O rings, which form a dihedral angle of 86.4 (2)°. In the crystal, O-H⋯O hydrogen bonds link the complex mol-ecules into a two-dimensional network parallel to (100). The di-methyl-formamide solvent mol-ecule is disordered about a twofold rotation axis.

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.

In the title compound, [Cu(C6H9N2O2)2], the Cu(II) atom is located on an inversion center and has a square-planar environment. Two 2-(hy-droxy-imino)-cyclo-hexan-1-one oxim-ate monoanions chelate to the Cu(II) atom and the Cu-N distances are 1.920 (3) and 1.930 (3) Å. There are two short intra-molecular O-H⋯O hydrogen bonds between the ligands. The complex mol-ecules stack into columns extended along the c axis, with a Cu⋯Cu distance between adjacent mol-ecules of 3.3060 (3) Å.

The combination of 1,2-cyclohexanedionedioxime (NioxH2) and carboxylate-containing ligands resulted in Zn(II) or Cd(II) robust metal building blocks which being coupled with the flexible pyridine ligands fabricated five one-dimensional (1D) coordination polymers {[Cd(CHOO)2(NioxH2)(bpe)]·DMF}∞ (1), [Cd(CHOO)2(NioxH2)(dps)]∞ (2), [Zn(CH3COO)2(NioxH2)(dps)]∞ (3), [Cd(CH3COO)2(NioxH2)(dps)]∞ (4), and {[Zn(pyta)2(NioxH2)]·DMF}∞ (5) (where bpe = 4,4′-bipyridine ethane, dps = 4,4′-dipyridylsulfide, Hpyta = (4-pyridylthio)acetic acid, DMF = N,N-dimethylformamide), whose crystal structures were determined by single crystal X-ray diffraction. The stability of compounds 1 and 5 to loss of DMF as a guest has been addressed experimentally, and the crystal-to-crystal transformation observed for 1 resulted in the guest free 1D polymer [Cd(CHOO)2(NioxH2)(bpe)]∞ (1a) which maintains its coordination network with the 10.3% unit cell volume contraction, while compound 5 remains unchangeable under the same conditions. Compounds 1, 5 and the dioxime-free 1D polymer [Cd(pyta)2(H2O)]∞ (6) display blue luminescence upon excitation with ultraviolet light. The emission intensity of the guest-loaded complex 1 is effectively reduced in comparison with the previously reported DMF free analogues [Zn(CH3COO)2(NioxH2)(bpe)(H2O)]∞ and [Cd(CH3COO)2(bpe)(H2O)]∞.