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Solvothermal reaction between CuI and 5-(3-pyridyl)tetrazole (HPTA) in CH3CN and NH3·H2O/n-BuOH, afforded two kinds of Cu7I4 cluster-based coordination polymers 1 and 2, respectively. 1 is a racemic conglomerate of enantiomers crystallizing in the P6322 space group and 2 is a mesomer crystallizing in the Pc1 group. Both 1 and 2 show dual-channel emissions in which low-energy emission originates from a cluster-centered (CC) excited state while high-energy emission is attributed to an iodide-to-ligand charge transfer (XLCT)/metal-to-ligand charge transfer (MLCT) excited state. Of particular interest, 2 exhibits thermochromic luminescence originating from the combined effects of non-radiative transition and thermal deactivation of the XLCT excited state.

The [2 + 2] photodimerization of tetrazolyl styrylpyridine leads to single-crystal-to-single-crystal transformations of four Zn(II) coordination polymers with 1D-3D structures, exhibiting controllable reaction extent, luminescence decrease or blue shift, and a two-step reaction process with a phase transition point.

As simulants of galactose oxidase (GO), three mononuclear Cu(II) complexes with 1-((3-t-Bu,5-R1)-salicylidenehydrazono),2-((3-t-Bu,5-R2)-salicylidenehydrazono)-1,2-diphenylethane (H2LBu,Bu: R1 = R2 = t-butyl; H2LMeO,MeO: R1 = R2 = methoxyl; H2LBu,MeO: R1 = t-butyl, R2 = methoxyl) as ligands were synthesized. X-ray diffraction defined their structures, like GO, all having a distorted square N2O2-coordinated Cu(II) center, and catalytic experiments confirmed their abilities to enable the aerobic oxidation of benzyl alcohol to benzaldehyde under room temperature with turnover numbers up to 823–1036. Voltammetric measurements indicated that the cupric phenolates are electroactive, in the range of 0.3–0.9 V (vs EFc+/Fc), all giving two anodic peaks symbolizing the formation of +1 and +2 charged complex radicals. The presence of radicals was proven by the thianthrene perchlorate titration UV–Vis spectra of 1–3 with showing two new absorptions typical for phenoxy radicals and by the electronic spin resonance spectra with revealing an antiferromagnetic coupling of phenoxy radicals with Cu(II) (s = 1/2).

Hydrothermal reactions of 1,2,4-triazole (Htrz) with CuBr or CuCl2 in the presence of benzene-1,3,5-tricarboxylic acid (H3btc) produced the infinite aggregates, [CuI4CuII2(trz)4(btc)Br] (1) and [CuI4CuII2(trz)4(btc)Cl] (2), composed of 2D mixed valent Cu-trz sheets, benzene-1,3,5-tricarboxylates and halides; in particular, the Br-labelled 1 crystallizes in I4/m space group with cell parameters: a = 20.321(2) A, b = 20.321(2) A, c = 13.699(1) A, V = 5714.8(4) A3 and the Cl-labelled 2 in a P4/ncc with a = 20.3711(5) A, b = 20.3711(5) A, c = 13.7711(8) A, V = 5656.9(6) A3. Solid measurements reveal that the halide-discriminated compounds are thermostable up to 300 °C and ambient luminescent, exhibiting the emission bands in the range of 400–550 nm.

To have an insight into the performance of chemically homogeneous but geometrically different isomeric ligands in constructing coordination polymers, two xylene-functionalized N-donors, specifically, p-BIMB and o-BIMB (BIMB = bis-(imidazol-1-ylmethyl)benzene), were treated, in parallel, with CuCN and KI under solvothermal conditions and with CuCl2 and NaN3 in layer diffusion, thereby affording four new coordination polymers with dimensions from 1D to 3D. In particular, the cuprous [Cu2(CN)2(p-BIMB)]n (1) is structured as a 3D framework showing an unprecedented bimodal (8 × 102)(85.10)2 topology and [Cu2(CN)2(o-BIMB)]n (2) as an undulated sheet based on a (CuCN)n network and the cupric {[Cu(N3)2(p-BIMB)2](H2O)2}n (3) is assembled as a 3D polycatenated framework based on the inclined interpenetrating (4,4) nets and [Cu(N3)2(o-BIMB)2]n (4) as a metal-fused ring catenation. The assemblies of 1−4 are of note for revealing a law that the polymers, comparably derived from two isomeric ligands, are similar in met...

The synthesis, single crystal structure, luminescent and electrochemistry properties of a Cu(I) compound based on in situ formation ligand, namely [1,2,3]triazolo[1,5-α]quinoline(L1), are reported. Complex [ Cu 4 I Br 4 ( L 1 ) 4 ] (1) is the first example of Cu(I) species with [1,2,3]triazole-ligand and provides the direct evidence for Cu(II) role to the ring-closure of hydrazone.

Three new coordination polymers, {[Zn(H2Bpz)(Tph)]·1/2(H2Bpz)}n (1), [Zn2(H2Bpz)(Bpz)(Iph)]n (2), and {[Zn2(H2Bpz)(HBtc)2(H2O)2]·7/6(H2O)}n (3) (H2Bpz = 3,3‘,5,5‘-tetramethyl-4,4‘-bipyrazole; H2Tph = terephthalic acid; H2Iph = isophthalic acid; H3Btc = benzene-1,3,5-tricarboxylic acid), have been isolated from parallel hydrothermal reactions of ZnSO4 and H2Bpz with H2Tph, H2Iph, and H3Btc, respectively. These crystalline solids have been structurally defined, of which 1 was revealed to construct in a 3D architecture with porosity. Interestingly, because of its large porosity, 1 allows the concurrent 2-fold interpenetration and inclusion of free H2Bpz as guest molecule. In contrast to 1, polymer 2 structures in a 2D framework of note for containing both neutral and deprotonated H2Bpz as μ2-and μ4-bridging linkers, respectively. This case demonstrates a rare usage of H2Bpz as ligand in the construction of MOFs. The partial deprotonation of H2Bpz may be a consequence of less acidity of H2Iph than H2Tph, by w...

Treatments of the MeOH, EtOH and PrOH solutions of 2-acetylpyridine, hydrazine and CuII salts (in molar ratio 2:3:2) afforded respectively the complexes, [CuII(HL)(Cl)](SO3CF3)H2O (1), [CuII(MeL)(H2O)](ClO4)2 (2) and [CuII(EtL)](Cl)](ClO4) (3) (L = bis-(methyl, 2-pyridyl ketone hydrazonyl)methine), in which the ligands, HL, MeL and EtL are formed in situ from oxidative couplings of alcohols and hydrazones.

Hydrothermal reactions of pyridyl-2,6-dicarboxylic acid (H2PDC) and NiCl2 · 6H2O in the presence of NaOH and KOH, respectively afforded the products, {[Ni(PDC)(Cl)](Na)(H2O)/3}n (1) and K2[Ni(PDC)2] · 7H2O (2), of which 1 was characterized consisting of 3-D porous framework and [Na6(H2O)]6+ inclusions, and 2 was a mononuclear complex with potassium hydrate as counterion.

Six 2D and 3D supramolecular complexes [Cu(L1)(O2CCH3)2] · H2O (1), [Cu2(L2)2(μ2-O2CCH3)2](BF4)2 (2), [Cu2(L1)2(BDC)(NO3)2] · 0.5H2O (3) [Cu2(L2)2(BDC)(NO3)2] (4), [Cu2(L3)2(BDC)(NO3)2] · 0.5H2O (5) and [Cu2(L2)2(BDC)(H2O)2](BDC) · 8H2O (6) (L1 = 4′-(4-pyridyl)-2,2′:6′,2″-terpyridine, L2 = 4′-(2-pyridyl)-2,2′:6′,2″-terpyridine, L3 = 4′-phenyl-2,2′:6′,2″-terpyridine, BDC = 1,4-benzenedicarboxylate), have been prepared and structurally characterized by X-ray diffraction crystallography. In complexes 1, 3, and 4, 1D channels are formed through C–H⋯O and C–H⋯N hydrogen-bonding interactions, and further linked into 3D structure via C–H⋯O and O–H⋯O interactions. Complex 2 is a 2D layer constructed from intermolecular C–H⋯F and π–π stacking interactions. In the structure of 6, the BDC2− ions and solvent water molecules form a novel 2D layer containing left- and right-handed helical chains via hydrogen-bonds, and an unusual discrete water octamer is formed within the layer. In 2, 4, 6 and [Ag2(L2)2](PF6)2 (7) the bonding types of pendent pyridines of L2 depending on the twist about central pyridines are involved in intramolecular (2 and 4), intermolecular (6) or coordination bonds (7) in-twist-order of 5.8°, 3.7°, 28.2° and 38.0°, respectively. Differently, the pendent pyridines of L1 in 1 and 3 form intermolecular hydrogen bonds despite of distinct corresponding twist angles of 25.1° (1) and 42.6°(3). Meanwhile, π–π stacking interactions are present in 1–6 and responsible for the stabilization of these complexes.

Seven copper complexes [Cu(L1)I2] (1), [Cu2(L1)2I2]2[Cu2(μ-I)2I2] (2), [Cu(L2)I2] (3), [Cu2(L2)(μ-I)I(PPh3)] (4), [Cu4(L2)2(μ-I)2I2] (5), {[Cu(L2)I]2[Cu2(μ-I)2I2]}n (6) and [Cu2(L2)(μ-I)2]n (7) have been prepared by reactions of ligands: 4′-(2-pyridyl)-2,2′:6′,2″-terpyridine (L1) and 4′-(3-pyridyl)-2,2′:6′,2″-terpyridine (L2) with CuI in hydrothermal conditions, respectively. By alternating the oxidations states of the metal centers, increasing stoichiometric metal/ligand ratio and introducing a second ligand, the compounds, were successfully developed from mononuclear (1 and 3) to multinuclear (2, 4 and 5) and polymers (6 and 7). The synthesis of these compounds may provide an approach for the construction of coordination compounds of 4′-pyridyl terpyridine with different nuclearity.

By the hydrothermal reactions of Nd2O3 with 2,2′-binicotinic acid (H2Bn) in the absence and presence of 4,4′-bipyridine(4,4′-bpy), two complexes, [Nd2(Bn)3(H2O)2]·4.5H2O (1) and [Nd2(Bn)3(H2O)2]·2H2O(4,4′-bpy) (2) were synthesized, of which the 4,4′-bpy-free 1 shows only the emissions based on Bn2 − within 300–500 nm, but the 4,4′-bpy-containing 2 shows also a band centered at 640 nm attributable to the exciplex [(4,4′-bpy)·Bn2 −]* coupled through π–π interaction.

A channel-equipped metal–organic framework, resulting from pyrolysis of [(CH3)2NH2]@[Eu2L3(HCOO)], showed the preferable absorption of CO2 and the Eu(iii)-based emission quenched by aromatics.

Three rare earth coordination polymers, {[Ln2(μ3-ADI)2(μ2-ADI)(H2O)4]·H2O}n (Ln = Tb, 1; Eu, 2; Er, 3; ADI = adipate), which show the inclined interpenetration of (4, 4) nets and bright luminescence, were isolated from H2PDC-assisted (H2PDC = pyridine-2,3-dicarboxylatic acid) hydrothermal reactions of H2ADI and Ln2O3.

Two three-dimensional coordination polymers, [(CuCN)3(4-pyBpy)]n (1) and [(CuCN)4(3-pyBpy)]n (2), as rare examples of coordination polymers of nonchelating quaterpyridines, demonstrating 4- and 2-fold interpenetrations, respectively, were isolated from solvothermal reactions of 2,6-bis(4-pyridyl)-4,4′-bipyridine (4-pyBpy) and 2,6-bis(3-pyridyl)-4,4′-biyridine (3-pyBpy) with CuCN in DMF and were structurally characterized.

A 3D coordination polymer, {[Cd15(μ4-Mtta)12(μ3-Mtta)6(μ3-SO4)4(μ3-OH)4] · 6H2O}n (1) (Mtta = 5-methyl-tetrazolate), which shows the rare multifunction of in situ formed Mtta and bright photo-induced blue emission, was isolated from a hydrothermal reaction of CdSO4 · 8/3H2O, NaN3 in acetonitrile and water.

By parallel hydrothermal reactions of 2,5-pyridinedicarboxylic acid (2,5-H 2 Pdc) and 2,6-pyridinedicarboxylic acid (2,6-H 2 Pdc) with 3,3′,5,5′-tetramethyl-4,4′-bipyrazole (Bpz) and ZnSO 4 · 7H 2 O, two novel zinc coordination polymers, [Zn(Bpz)(2,5-Pdc)] n ( 1 ) and [Zn 2 (Bpz)(2,6-Pdc) 2 ] n ( 2 ), which contain in situ formed [Zn(Pdc)] n helices as building blocks and exhibit photoluminescent at room temperature, were synthesized respectively.

Four cubane-like Cu4I4 units are assembled around an iodine atom to form the giant, mixed-valent Cu(II)Cu(I)15I17 cluster. The Cu(II)Cu(I)15I17 cluster and a bipyrazole linker form a 3D open framework with paramagnetic and thermochromic properties. This paper also touches on the resemblance of this cluster to the self-similar object of a Sierpinski tetrahedron.

A complex, [Cd(BIMB)0.5SO4(H2O)2]n · nH2O (1) was synthesized by solvothermal reaction of 1,4-bis(imidazol-1-ylmethy)benzene (BIMB) with CdSO4 · 8/3H2O and was revealed a photoluminescent 3-D metal-organic framework (MOF), assembled from 2-D Cd(II)– SO 4 2 - coordination sheets and trans configured BIMBs.

X-ray crystal studies on Ni(II) complexes, [Ni(LI)2](Cl)2(H2O) (1) (LI = diethylenetriamine) and [Ni(LII)](Cl)(H2O) (2) (LII = N-(2-(naphtholate)methine)diethylenetriamine) reveals a new type of hydrogen-bonded chains [ ⋯ Cl ⋯ H – O – H ] n n - , existing in both 1 and 2 as paired M and P helices with 2-fold screw axes parallel to b, and thermal analysis of 1 reveals that the water molecules in chains evaporate at 105 °C accompanied by an enthalpy change of 27.2 kJ mol−1.

Treatment of the methanolic solution of 2-(2-hydroxyphenyl)-1,3-bis[4-(2-hydroxy-phenyl)-3-azabut-3-enyl]-1,3- imidazoline (H3L) and ZnSO4 · 7H2O affords the solvated multiplex [Zn2(SO4)(L)]2[Zn(H2O)6] · 3H2O · 0.75CH3OH (1) which uniquely contains anionic dizinc complexes of L3− as components and shows photoluminescence at room temperature.

In the crystal structure of the title compound, [Cu(C7H3NO4)(NH3)2], the Cu atom is coordinated in a square-pyramidal geometry by a pyridine-2,6-dicarboxyl­ate ligand acting in an N,O,O′-tridentate chelating mode, and by two N atoms from two ammine ligands. A further long Cu—O bond involving a symmetry-realated mol­ecule generates chains of mol­ecules in the a-axis direction.

The title compound, {[Zn(C8H4O4)(C21H15N3)]·H2O}n, is a one-dimensional polymeric complex bridged by centrosymmetric dicarboxyl­ate dianions. Each Zn atom is five-coordinate, bonded to two carboxyl O atoms from the dicarboxyl­ate dianions and to three N atoms from the heterocycle, which chelates to the Zn atom in a κ3N,N′,N′′ manner.

The title compound, [Cu(C8H4O4)(C21H15N3)]·C8H6O4, consists of polymeric chains in which the terpyridine heterocycle chelates to the Cu atom in an N,N′,N′′-tridentate manner; the Cu atoms are also covalently bonded through the two singly-bonded carboxyl O atoms of the dicarboxyl­ate dianions to give rise to a chain structure. An additional terephthalic acid molecule is hydrogen bonded to the chains. The asymmetric unit contains halves of two different half-molecule terephthalate ions; in each case, the complete ions are generated by inversion symmetry.

Solvothermal reactions of CuSCN, metal (Mn 2+ , Fe 2+ , Co 2+ , Ni 2+ , Cu 2+ ) sulfate, and terpyridine (2,2':6',2"-terpyridine or 4'-p-tolyl-2,2':6',2"-terpyridine) in the presence of triphenylphosphine yielded a series of hybrid coordination compounds, in which in situ formed metal bis(terpyridine) complex cations are encapsulated by a 3D anionic network or entangled by 2D heartlike networks, forming encapsulation or polypseudorotaxane supramolecules. The complex cations play a role as template to direct the fabrication of the structures.

The supramolecular host molecule N,N′,N′-tris(ruthenocenylmethyl)-1,4,7-triazacyclononane perchlorate [LH] ClO4 was prepared and its molecular structure was determined by single crystal X-ray analysis. The guest proton was localized on one of the aza atoms of the macrocycle (NH : 0.71 A). Cyclic voltammetric measurement displays in irreversible oxidation wave at 0.84 V and is attributable to the oxidation of RuII to RuIII of the appended metallocenes.

Six mixed-valence Cu(I)Cu(II) compounds containing 4'-(4-pyridyl)-2,2':6',2' '-terpyridine (L1) or 4'-(2-pyridyl)-2,2':6',2' '-terpyridine (L2) were prepared under the hydrothermal and ambient conditions, and their crystal structures were determined by single-crystal X-ray diffraction. Selection of CuCl(2).2H(2)O or Cu(CH(3)COO)(2).H(2)O with the L1 ligand and NH(4)SCN, KI, or KBr under hydrothermal conditions afforded 1-dimensional mixed-valence Cu(I)Cu(II) compounds [Cu(2)(L1)(mu-1,1-SCN)(mu-Cl)Cl](n) (1), [Cu(2)(L1)(mu-I)(2)Cl](n) (2), [Cu(2)(L1)(mu-Br)(2)Br](n) (3), and [Cu(2)(L1)(mu-1,3-SCN)(2)(SCN)](n)(4), respectively. Compound 5, prepared by layering with CuSCN and L1, is a 2-dimensional bilayer structure. In compounds 1-5, the L1 ligand and X (X = Cl, Br, I, SCN) linked between monovalent and divalent copper atoms resulting in the formation of mixed-valence rectangular grid-type M(4)L(4) or M(6)L(6) building blocks, which were further linked by X (X = Cl, Br, I, SCN) to form 1- or 2-dimensional polymers. The sizes of M(4)L(4) units in 1-4 were fine-tuned by the sizes of X linkers. Reaction of Cu(CH(3)COO)(2).H(2)O with L2 and NH(4)SCN under hydrothermal conditions gave mixed-valence Cu(I)Cu(II) compound [Cu(2)(L2)(mu-1,3-SCN)(3)](n) (6). Unlike those in 1-5, the structure of 6 was constructed from thiocyanate groups and the pendant pyridine of L2 left uncoordinated. The temperature-dependent magnetic susceptibility studies on compounds 1 and 4 showed the presence of mixed-valence electronic structure.

In the title compound, [Cu(NCS)(C20H14N4)]SCN, the Cu atom is four-coordinated by a tridentate chelating 4′-(2-pyridyl)-2,2′:6′,2′′-ter­pyridine ligand and one isothio­cyanate group in a square-planar coordination geometry. The sum of angles around the CuII center is 359.1°.

The Zn atom in each of the two symmetry-independent complex molecules of the title compound, [ZnCl2(C21H15N3)]·H2O, shows trigonal-bipyramidal coordination as the N-heterocycle is able to span the two axial sites of the coordination polyhedron. One of the molecules occupies a position in the crystal structure such that it does not interact with any water mol­ecule; the other interacts with two water mol­ecules to give rise to a hydrogen-bonded chain that runs along the a axis of the triclinic unit cell.

The Cu atom in the 1/1 adduct of copper(II) diiodide with 4′-phenyl-2,2′:6′,2′′-ter­pyridine, [CuI2(C21H15N3)], exists in a square-pyramidal environment. The Cu—Iaxial bond [2.7872 (9) A] is significantly longer than the Cu—Ibasal bond [2.5394 (8) A].

In the title complex, [Ag(C2H3N)(C21H15N3)]PF6·CH3CN, the AgI atom is coordinated by a tridentate chelating 4′-phenyl-2,2′:6′,2′′-terpyridine ligand and an aceto­nitrile mol­ecule, to form a distorted square-planar geometry.

Methanothermal reactions of CuI and 2,2′-biimidazole in the molar ratios of 1 : 1 and 3 : 4 gave the luminescent coordination polymers, [Cu8(μ2-I)(μ3-I)6(μ6-I)(1,1′-DMBIM)3]n (1), as a knotted rope, and [Cu4(μ3-I)4(1,3-DMBIM)2]n (2), as a setup of two interpenetrating 66-dia networks (DMBIM = dimethyl-2,2′-biimidazole).

To systematically investigate the effect of the pendant groups of ligands on the assembly of coordination polymers (e.g, controlling interpenetration), four terpyridine ligands with bulky pendant groups, namely, 4′-(4-tolyl)-4,2′:6′,4′′-terpyridine (L1), 4′-(4-ethylphenyl)-4,2′:6′,4′′-terpyridine (L2), 4′-(4-isopropylphenyl)-4,2′:6′,4′′-terpyridine (L3), and 4′-biphenyl-4,2′:6′,4′′-terpyridine (L4) have been synthesized for comparative purposes. The reactions of CuCN and L1–L4 under the same solvothermal conditions provided four CuCN coordination polymers: [(CuCN)2L1]n (1), [(CuCN)2L2]n (2), [(CuCN)2L3]n (3), and {[(CuCN)3L41.5]·H2O}n) (4), respectively. Single-crystal X-ray analyses reveal that compounds 1–3 are isostructural with the same topological 4-fold interpenetrated 3D CuCN networks, and compound 4 is a non-interpenetrated CuCN network. This success demonstrates that the interpenetration is suppressed by the alteration of the size of the pendant groups of terpyridine ligands.

This paper reports two structurally unique CuCN-terpyridine hybrid networks of 4′-p-tolyl-2, 2′ : 6′, 2″-terpyridine (ttpy) prepared under solvothermal condtions: [(CuCN)5(ttpy)]n (1), [(CuCN)3(ttpy)]n (2). Complex 1 features a tri-layer structure with 3-connected binodal (8210)·(8210) topology, while complex 2 features unusual honeycomb-like layer structures. The adjacent honeycomb-like layers consist of the opposite handed helical CuCN-ttpy chains. In both complexes, each ttpy coordinates two copper(I) atoms with short Cu–Cu distances, and the side pyridyl group rotates in a certain angle from the central pyridyl plane directing the formation of the diversified networks.

Two luminescent coordination compounds, [Cu(Pz)]3 (1) and [Cu2(Bpz)]n (2), were isolated from solvothermal reactions of Cu(NO3)2 with 3,5-dimethylpyrazole (HPz) and 3,3',5,5'-tetra-methyl-4,4'-bipyrazole (H2Bpz) respectively in the presence of NH3, of which 1 was revealed to be a planar trimer and 2 a three-dimensional framework, presenting a rare 3-connected binodal (6(2).10)(6.10(2)) topology and eight-fold interpenetration.