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Nine Cu(I)-cyanide metal-organic frameworks (MOFs), namely, [Cu4(CN)2(4-bpt)2]n (1), {[Cu3(CN)2(4-bpt)]·H2O}n (2), [Cu2(CN)(3-bpt)]n (3), [Cu2(CN)2(3-Hptz)]n (4), [Cu3(CN)2(3-ptz)]n (5), [Cu7(CN)7(3-tpt)2]n (6), {[Cu9(CN)9(btb)2]·btb}n (7), [Cu2(CN)2(4-azpy)]n (8), and [Cu3(CN)3(bpp)]n (9) (4/3-Hbpt = 3,5-bis(4/3-pyridyl)-1,2,4-triazole; 3-Hptz = 3-pyridyl-tetrazole; 3-tpt = 2,4,6-tris(3-pyridyl)-1,3,5-triazine; btb = 1,4-bis(1,2,4-triazol-4-yl)benzene; 4-azpy = 4,4'-azobispyridine; bpp = 1,3-bis(4-pyridyl)propane), were synthesized under hydrothermal conditions and structurally characterized. The 4-bpt, 3-bpt, and 3-Hptz ligands in 1-4 were in situ generated by cycloaddition reactions. Their structural features vary from two-dimensional (2D) (3), three-dimensional (3D) (4, 5, 6), 3D 2-fold interpenetration (1, 2, 8), to 3D 3-fold interpenetration (7, 9). Complex 1 is an intriguing 3D metal-organic framework (MOF) with a nanosized rectangular channel. Complex 3 exhibits a chiral 2D double-layered network prepared by achiral component. Complex 6 is a 3D MOF constructed from six μ2-cyanides, a μ3-cyanide, and a μ3-tpt ligand. Complex 7 shows an interesting 3D MOF with (3.4)-connected 5-nodal net, containing a btb guest molecule in the rectangular channel. Complex 8 is a 3D MOF assembled by a 2D [Cu2(CN)2]n network pillared by a 4-azpy spacer. Complex 9 is a 3D MOF with ths topology. Their structural diversity originates from the variation of Cu(I) coordination numbers and three types of cyanide-bridging modes, tuned via various bidentate (4-azpy, bpp), tridentate (3-Hptz, 3-tpt), and tetradentate (4-bpt, 3-bpt, 3-ptz, btb) N-heterocyclic ligands. Infrared spectra and cyanide coordination modes are discussed in detail. The characteristic ν(C≡N) stretching frequencies in μ2-CN complexes show linear correlation with the Cu-CN bond distances. A decrease of about 6.7 cm-1 in ν(C≡N) corresponds to a 0.01 Å elongation of the Cu-CN bond. These Cu(I) complexes exhibit good thermally stability and emit strong luminescence at 386-593 nm. [ABSTRACT FROM AUTHOR]

Metal salts and 3/4-pyridyltetrazoles (3/4-Hptz) react with oxalic acid (H2ox), 1,2,4,5-benzenetetracarboxylic acid (H4btec), isophthalic acid (H2ip), and 1,2,3,4-butanetetracarboxylic acid (H4btca) to afford six coordination polymers, namely, [Cu(4-ptz)(ox)0.5]n (1), [Cu(4-Hptz)(btec)0.5]n (2), [Co2(3-ptz)(ip)(OH)(H2O)]n (3), {[Co1.5(3-ptz)(btca)0.5(H2O)]·H2O}n (4), {[Co3(4-ptz)2(btca)(H2O)3]·2H2O}n (5), and {[Cd2(4-ptz)2(btca)0.5(H2O)3]·DMF·4H2O}n (6). Their structures were characterized by EA, IR, PXRD, TGA, and single-crystal XRD. 3/4-Pyridyltetrazoles display μ2-, μ3-, and μ5-coordination modes in them. Complex 1 is a 3D MOF constructed from a 2D (4,4) [Cu(4-ptz)]n grid pillared by an oxalate spacer. Complex 2 displays a 2D network containing a square planar Cu1 and elongated octahedral Cu2 centers. Complex 3 shows a 2D network containing μ5-ptz, μ3-ip, and μ3-OH. Complex 4 exhibits a 3D MOF assembled by a 2D [Co1.5(btca)0.5]n network pillared by a 3-ptz spacer. Complex 5 displays a 3D porous MOF with nanosized rectangular tunnels. Complex 6 features a 3D porous MOF built by 2D [Cd2(4-ptz)(btca)0.5]n network pillared by a 4-ptz spacer. Variable-temperature magnetic susceptibility and magneto-structural correlation studies indicate that five CuII/CoII complexes present remarkable magnetic coupling diversity from ferro-, to ferri-, to antiferromagnetic interactions. Complex 1 shows strong antiferromagnetic behavior originating from the oxalate-bridging CuII dimer (Jox = −94.7 cm-1) and the tetrazole-bridging CuII dimer (Jptz = −61.0 cm-1). Complex 2 presents a weak ferromagnetic interaction (J = 0.82 cm-1) originating from the magnetic orbital orthogonality between square planar CuII and octahedral CuII centers. Complex 3 displays ferrimagnetic coupling in the Co3(μ3-OH) triangle. Two btca CoII complexes show antiferromagnetic interactions originating from carboxyl-bridging trinuclear CoII clusters with the θ values of −17.08 K for 4 and −8.6 K for 5. The thermal behaviors of these nitrogen-rich tetrazole complexes are investigated. Anhydrous complexes 1-3 containing rigid polycarboxylates are thermally stable to 250-300 °C and then decompose explosively, whereas complexes 4-6 with flexible butanetetracarboxylate decompose smoothly. [ABSTRACT FROM AUTHOR]

Six zinc metal–organic frameworks,namely, [Zn(bpmb)(HCOO)]n·[Zn(bpmb)(OH)]n·4nH2O (1), [Zn(bpmb)(HCOO)]n(2), [Zn2(bpmb)2(fum)]n·9nH2O (3), [Zn3(bpmb)2(d-cam)2]n(4), [Zn2(bpmb)(1,3,5-btc)]n·nDMA (5), and [Zn(bpmb)(1,2,4,5-H2btec)]n·4nH2O (6) (Hbpmb = 3,5-bis(4-pyridylmethoxy)benzoicacid; H2fum = fumaric acid; d-H2cam= d-camphoric acid; 1,3,5-H3btc = 1,3,5-benzenetricarboxylicacid; 1,2,4,5-H4btec = 1,2,4,5-benzenetetracarboxylic acid;DMA = N,N-dimethylacetamide), weresynthesized under solvothermal conditions. Their structures were characterizedby EA, IR, PXRD, TG, and single-crystal XRD. Complex 1is constructed of two independent neutral 3D MOFs with large 1Dnanosized square channels, which are further entangled by each otherto give an unexpected 4-fold [2 + 2] interpenetrating architecture.Complex 2is a 3D MOF constructed from tetradentate bpmband bidentate formate ligands, which is an isomer of the [Zn(bpmb)(HCOO)]npiece in 1. Complex 3displays a 2D double-layered network that possesses 1D nanosizedpores. Each 2D double layer is further interlocked with two neighboringones to form an interesting 3D polycatenation array. Complex 4possesses a 2D network constructed from a trinuclear [Zn3(COO)6N4] cluster and Zn–camdouble-helical chain. Complex 5is a 3D porous MOF constructedfrom tridentate bpmb and hexadentate 1,3,5-btc ligands. Complex 6exhibits a 2-fold interpenetrating 2D wavelike (4,4) networkconstructed from bidentate bpmb and 1,2,4,5-H2btec ligands.The bpmb ligand adopts four types of coordination modes in 1–6. The secondary carboxylate ligands have obviouseffects on their coordination architectures. Tetrahedral-, octahedral-,and trigonal-bipyramidal geometries around Zn(II) ions are observed.A general solvothermal method is proposed for preparing carboxylatecomplexes in DMF−H2O solution without any basicadditive. In the preparation of 3, maleic acid is convertedto a fumarate ligand. The thermal stabilities of six complexes andN2adsorption behaviors of 1and 3are investigated. All the Zn(II) complexes emit blue luminescenceoriginating from ligand-centered emission. [ABSTRACT FROM AUTHOR]

In order to tune the Zn(II) coordinationpolymer architectures,three position isomers, 1,4- (pbtmb), 1,3- (mbtmb), and 1,2-bis(1,2,4-triazol-1-ylmethyl)benzene(obtmb), and flexible tetracarboxylate ligand, 5,5′-(1,4-phenylenebis(methylene))bis(oxy)diisophthalicacid (H4L1), were used to assemble compounds with different kindsof entangled networks, namely, {[Zn2(L1)(pbtmb)2]·4H2O}n(1), {[Zn2(L1)(mbtmb)2]·4H2O}n(2), and [Zn2(L1)(obtmb)2]n(3). Flexible bis(triazole) ligands present diverseconformations in these compounds. Compound 1shows a4-fold interpenetrating three-dimensional architecture with 4-connectedmog (moganite) topology. Compound 2displays a 2D + 2D→ 3D polycatenation network simplified as new 4-connected topologywith the Schlafli notation of {4,64;8}2{42,64}. Compound 3is a 2D polythreadingstructure, in which two layed networks interpenetrate in a (2D/2D)parallel fashion. The powder X-ray diffraction, thermal stabilities,and the photoluminescence of 1–3havealso been investigated. [ABSTRACT FROM AUTHOR]

Seven novel coordination polymers based on 2,2′-phosphinico-dibenzoic acid (H3L), namely, {[Zn3L2(H2O)4]·2H2O}n (1), [Zn3L2(4,4′-bipy)2]n (2), [Zn(HL)(2,2′-bipy)(H2O)]n (3), {[Cd9L6(H2O)8]·4H2O}n (4), [Cd8L4(OH)2(OAc)2(4,4′-bipy)]n (5), [Mn3L2(4,4′-bipy)(EtOH)(H2O)2]n (6), and [Mn(HL)(2,2′-bipy)(H2O)]n (7), were synthesized under hydro(solvo)thermal conditions. These compounds crystallize in the triclinic P1̅ space group for 1, 4, 5, and 6, the monoclinic space group C2/c for 2, and the monoclinic P21/c space group for 3 and 7. The L3- ligand displays versatile binding modes in 1-7. Compound 1 is a one-dimensional (1-D) chain coordination polymer with a three-dimensional (3-D) supramolecular framework. Compound 2 is a 3-D porous metal-organic framework (MOF) with two different 4,4′-bipyridine linkers. Compounds 3 and 7 show 1-D zigzag chain structures. Compound 4 exhibits a sophisticated 3-D MOF constructed from two types of Cd8 clusters and one Cd2 dimer, which is the first example exhibiting the coexistence of four coordination modes of L3- ligands and four geometries of Cd(II) ions in one network. Compound 5 displays a two-dimensional (2-D) network containing a ring-like Cd8 cluster. Compound 6 shows a 2-D layered network with 4,4′-bipyridine linker. Their luminescence and variable-temperature magnetic property were investigated, which indicated ligand-centered emission in 1-5 and weak antiferromagnetic coupling between Mn(II) ions in 6 and 7. [ABSTRACT FROM AUTHOR]

The hydrothermal/solvothermal reactions of metal(II) nitrate hydrates with organic ligands (p-benzenediacrylic acid = H2pbda, 1,10-phenanthroline = phen) generate three three-dimensional (3-D) coordination polymers with (3,4)-connected (4.8.10)(42.6.8 × 102) topology (1, {[Cd2(pbda)2(phen)2](H2O)}n), 2-fold interpenetrating CdSO4-type open framework (2, [Zn3(pbda)3(phen)2]n), and 3-fold interpenetrated sra net (3, [Pb(pbda)]n). The porous zinc open framework 2 has the typical type-I sorption curve with a H2 uptake of 31 cm3·g−1(STP) at 77 K, BET surface area of 65.84 m2·g−1, and meso-[Zn2(pbda)2] helical motifs. With strong luminescent emission at 504 nm, complex 2 may be suitable as an excellent candidate for solid-state photosensitive materials at room temperature. Three-dimensional {[Cd2(pbda)2(phen)2](H2O)}n (1), [Zn3(pbda)3(phen)2]n (2), and [Pb(pbda)]n (3) are reported (H2pbda = p-benzenediacrylic acid, phen = 1,10-phenanthroline). Topologies of three metal(II)-organic coordination polymers are investigated. Complex 2 has the typical type-I sorption curve with a H2 uptake of 31 cm3·g−1(STP) at 77 K and luminescent emission at 504 nm at room temperature. [ABSTRACT FROM AUTHOR]