Zhenzhong Lu

Solvatochromic Behavior of a Nanotubular Metal−Organic Framework for Sensing Small Molecules

A nanotubular metal-organic framework (MOF), {[(WS(4)Cu(4))I(2)(dptz)(3)]·DMF}(n) (dptz = 3,6-di(pyridin-4-yl)-1,2,4,5-tetrazine, DMF = N,N-dimethylformamide) for sensing small solvent molecules is presented. When accommodating different solvent molecules as guests, the resulting inclusion compounds exhibit different colors depending on the solvent guests, and more interestingly, the band gaps of these solvent-included complexes are in linear correlation with the polarity of the guest solvents. The solvent molecules can be sensed by the changes of UV-vis spectra of the corresponding inclusion compounds, showing a new way of signal transduction as a new kind of sensor. The sensing by such a MOF occurs within the channel-containing material rather than on the external surface.

A microporous metal–organic framework with FeS2 topology based on [Zn6(μ6-O)] cluster for reversible sensing of small molecules

The first luminescent metal-organic framework (MOF) with [Zn(6)(μ(6)-O)] cluster has been synthesized and realized for reversible sensing of small molecules.

Cobalt-promoted B-H and C-H activation: facile B-C coupling of carboranedithiolate and cyclopentadienyl.

We report the one-pot reactions of the 16e(-) half-sandwich complex CpCoS(2)C(2)B(10)H(10) (1), methyl propiolate, and 3e(-)-donor ligands, which lead to selective B-functionalization at carborane with cyclopentadienyl as a functional group at ambient temperature in good yields. Metal-promoted activations of both a B-H bond of the carborane and a C-H bond of the Cp unit take place sequentially in the cooperation of organic ligands. The reaction requires a 3e(-)-donor ligand and an activated alkyne and is therefore suitable for a broad range of substrates. This investigation provides a simple and efficient synthetic route to B-functionalized carborane derivatives.

Metal–Organic Frameworks Constructed from Versatile [WS4Cux]x−2 Units: Micropores in Highly Interpenetrated Systems

Five metal-organic frameworks (MOFs) formed by [WS(4)Cu(x)](x-2) secondary building units (SBUs) and multi-pyridyl ligands are presented. The [WS(4)Cu(x)](x-2) SBUs function as network vertexes showing various geometries and connectivities. Compound 1 contains one-dimensional channels formed in fourfold interpenetrating diamondoid networks with a hexanuclear [WS(4)Cu(5)](3+) unit as SBU, which shows square-pyramidal geometry and acts as a tetrahedral node. Compound 2 contains brick-wall-like layer also with a hexanuclear [WS(4)Cu(5)](3+) unit as SBU. The [WS(4)Cu(5)](3+) unit in 2 is a new type of [WS(4)Cu(x)](x-2) cluster unit in which the five Cu(+) ions are in one plane with the W atom, forming a planar unit. Compound 3 shows a nanotubular structure with a pentanuclear [WS(4)Cu(4)](2+) unit as SBU, which is saddle-shaped and acts as a tetrahedral node. Compound 4 contains large cages formed between two interpenetrated (10,3)-a networks also with a pentanuclear [WS(4)Cu(4)](2+) unit acting as a triangular node. The [WS(4)Cu(4)](2+) unit in 4 is isomeric to that in 3 and first observed in a MOF. Compound 5 contains zigzag chains with a tetrahedral [WS(4)Cu(3)](+) unit as SBU, which acts as a V-shaped connector. The influence of synthesis conditions including temperature, ligand, anions of Cu(I) salts, and the ratio of [NH(4)](2)WS(4) to Cu(I) salt on the formation of these [WS(4)Cu(x)](x-2)-based MOFs were also studied. Porous MOF 3 is stable upon removal and exchange of the solvent guests, and when accommodating different solvent molecules, it exhibits specific colors depending on the polarity of incorporated solvent, that is, it shows a rare solvatochromic effect and has interesting prospects in sensing applications.

Synthesis and properties of five unexpected copper complexes with ring-cleavage of 3,6-di-2-pyridyl-1,2,4,5–tetrazine by one pot in situhydrothermal reaction

Solvothermal reactions of CuSO4·6H2O and Cu(Ac)2·H2O with 3,6-di-2-pyridyl-1,2,4,5-tetrazine (DPTZ) in the presence of different acetonitrile/water ratios (from 1:3 to 3:1) and temperatures (from 40 to 120 °C) successfully produce five coordination polymers: [Cu4(SO4)2(H2O)5(L2)2] (1), [Cu2SO4(H2O)3(L2)] (2), [Cu2(μ-CN)2(L1)] (3), [Cu2(bdc0.5)2(L2)(H2O)] (4, H2bdc = p-phthalic acid) and [Cu(L3)2] (5) (the known mononuclear compound). Unexpectedly three ligands: 2,5-bis(2-pyridyl)-1,3,4-oxodiazole (L1), N-bis-(R-hydroxyl-2-pyridyl)ketazine (H2L2) and pyridine-2-carboxylate (HL3), were obtained through NN bond cleavage of DPTZ. Complexes 1, 2 and 3 own one-dimensional (1D) structures, complex 4 shows a two-dimensional (2D) framework. The new compounds were characterized by elemental analysis, IR spectroscopy, and X-ray single-crystal diffraction. We focus our study on the ring-opening reaction mechanism, the occurrence process of CuII → CuI, the C–CN cleavage reaction of acetonitrile under lower temperatures (40–60 °C) and the influence of temperature and the ratio of solvent. In addition, magnetic susceptibility measurements indicate that 1, 2 and 4 show strong antiferromagnetic interactions between the adjacent CuII ions.

Organic–inorganic hybrid coordination polymers based on the 5-oxyacetate isophthalic acid (H3OABDC) ligand: syntheses, structures, magnetic and luminescent properties

Five new complexes, [Ln(OABDC)(H2O)5]n·2nH2O [Ln = Sm (1), Eu (2), Dy (3)], [Ni4(OABDC)2(OH)2(H2O)4]n·4nH2O (4), [Cu2(OABDC)(4,4′-bipy)0.5(OH)]n (5) have been synthesized by the hydrothermal reaction of a unique scorpion-shaped carboxylate ligand (5-oxyacetate isophthalic acid = H3OABDC) with different lanthanide or transition metals in the presence or absence of auxiliary 4,4′-bipyridine ligand. Their structures have been determined by single-crystal X-ray diffraction analysis and further characterized by elemental analysis, IR spectra, and thermogravimetric analysis. Compounds 1–3 are isostructural: the metal ions are bridged through carboxylate oxygen atoms to form 1D zigzag chains, and adjacent chains are further extended to a 3D supramolecular structure via hydrogen bonds. Compound 4 has a two-dimensional (2D) metal–organic framework based on [Ni4(μ3-OH)2]6+ clusters, which are further connected by intermolecular hydrogen bonds to form a 3D network. In compound 5, multicarboxylate ligands link Cu centers to generate a 2D sheet structure which is further connected by auxiliary 4,4′-bipyridine ligand to form a 3D structure. Free H3OABDC ligand and complexes 1, 2 exhibit strong fluorescent emissions in the visible region. Magnetic susceptibility measurements indicate that 4 exhibits weak ferromagnetic coupling between adjacent Ni(II) ions, whereas 5 shows antiferromagnetic coupling between Cu(II) ions.

Application of W–Cu–S-based secondary building units in functional metal–organic frameworks

This highlight discusses the structures and functions of W–Cu–S cluster polymers divided into different multinuclear cluster units. Great strides have been made in the potential applications of W–Cu–S cluster polymers in advanced materials, including third-order non-linear optics (NLO), gas absorption and solvatochromic effects, in the past few years. Finally, we suggest some opportunities to further improve the depth of the related research.

CCDC 831079: Experimental Crystal Structure Determination

Related Article: Jiehu Cui, Liangfang Huang, Zhenzhong Lu, Yizhi Li, Zijian Guo, Hegen Zheng|2012|CrystEngComm|14|2258|doi:10.1039/c2ce05785a