Fang-Ming Wang

Construction of three metal-organic frameworks based on multifunctional T-shaped tripodal ligands (4,5-dicarboxy-1H-imidazol-2-yl)pyridine-1-oxide

Three metal-organic frameworks, [Eu(C10H6N3O5)3(H2O)2]u2009·u2009H2O (1), [Tb(C10H6N3O5)3(H2O)2]u2009·u2009H2O (2), and [Cd(C10H6N3O5)2Cl2] (3) based on T-shaped tripodal ligands 3-(4,5-dicarboxy-1H-imidazol-2-yl)pyridine-1-oxide and 4-(4,5-dicarboxy-1H-imidazol-2-yl)pyridine-1-oxide (H3DCImPyO), have been synthesized by the hydrothermal method and characterized by elemental analysis, IR, and single-crystal X-ray structure analysis. The diverse coordination modes of H3DCImPyO ligands have afforded the three compounds. Complexes 1 and 2 are isomers and the Ln (Lnu2009=u2009Eu or Tb) atoms have coordination number eight with a distorted square prism geometry. The partly deprotonated H2DCImPyO− ligands display three different coordination modes to link Ln (Lnu2009=u2009Tb or Eu) into 1-D double chains. In 3, Cd(II) lies on an inversion center and displays a slightly distorted octahedral coordination. All three compounds exhibit strong fluorescent emissions in the solid state at room temperature.

Crystal structure, magnetism, and dielectric properties based on the axially chiral ligand 2,2′-dinitro-4,4′-biphenyldicarboxylic acid

Six novel metal–organic-frameworks (MOFs), [Ni(nbpdc)(4,4′-bpy)(H2O)]n (1), [Ni2(nbpdc)2(4,4′-bpy)2(H2O)2]n (2), [Ni(nbpdc)(4,4′-bpy)]n (3), [Mn(nbpdc)(4,4′-bpy)]n (4), [Co(nbpdc)(4,4′-bpy)]n (5), and [Zn2(nbpdc)2(4,4′-bpy)]n (6), with different crystal structures and divalent cations (Zn(II), Ni(II), Mn(II), and Co(II)) from the same ligands nbpdc and 4,4′-bpy (H2nbpdc = 2,2′-dinitro-4,4′-biphenyldicarboxylic acid, 4,4′-bpy = 4,4′-bipyridine) have been synthesized and characterized. Complex 1 showed a new point group of 222 and a new topology structure of sqc6. Crystal structures of complexes 2–6 with the same nonpolar point group of 2/m were determined by single-crystal X-ray diffraction. Complex 2 exhibited a rare three-interlude 3D structure with (44·62)(48·66·8) topology. Complexes 3–5 featured the same topology structure of (44·610·8)(44·62). Complex 6 had a 3D framework with (10)(6·82·103·124)2(62·8)2(8)2 topology. In addition, complex 1 displayed commendable adsorption of N2 at room temperature. 4 and 5 showed antiferromagnetism. Moreover, all six MOFs displayed abnormal dielectric peaks from 225 K to 275 K, which were measured at various frequencies and temperatures.

Syntheses, crystal structures and properties of inorganic–organic hybrids constructed from Keggin-type polyoxometalates and silver coordination compounds

Four inorganic–organic hybrids based on polyoxometalates (POMs), [Ag4(btz)2(Hbtz)2(H2O)Na(PMo12O40)·H2O] (1), [Ag2(4,4′-bpy)2Ag2(4,4′-bpy)(H2O)2(PMoVMoVI11O40)] (2), [Ag5(btz)2(4,4′-bpy)2(PMo12O40)·3H2O] (3), and [Ag5(btz)2(4,4′-bpy)2(PW12O40)·3H2O] (4) (Hbtz = 1H-1,2,3-benzotriazole, 4,4′-bpy = 4,4′-bipyridine), have been hydrothermally synthesized and structurally characterized by conventional techniques. Compound 1 is a 2D layer composed of AgI ions, btz ligands and [PMo12O40]3− anions. Compound 2 represents a rare 3D poly-threading framework based on infinite 2D layers made up of {POM–Ag2} inorganic building blocks and bpy ligands, which were threaded by silver–organic linear double chains. Compounds 3 and 4 are isostructural and exhibit three-fold interpenetrating diamondoid frameworks containing tri-nuclear silver centers as nodes and hexa-nuclear silver–organic macrocycles and [PMo12O40]3− anions, both as bi-connected units. Furthermore, their electrochemical properties, fluorescence properties and optical band gaps have been investigated in detail.

Prolonging luminescent lifetimes by introducing bis(maleonitriledithiolato)metalate anions with a fluorescent organic cation

A new organic fluorescent ionic compound [MOBIP]I (1) (MOBIP+u2009=u20091-methyl-2-oxo-3u2009-(1H-benzimidazol-2(3H)-ylidene)-2,3-dihydropyridinium) was synthesized and used to prepare seven maleonitriledithiolate metal complexes [MOBIP] n [M(mnt)2] by substitution of the iodide ion with [M(mnt)2] n − (Mu2009=u2009Cu2+ (2), Ni2+ (3a), Ni3+ (3b), Zn2+ (4), Cd2+ (5), Pd2+ (6), and Pt2+ (7)). An investigation of fluorescence properties shows that these complexes are a new series of solution luminescent complexes of maleonitriledithiolate derivatives with strong blue light fluorescence in daylight by irradiation with UV light with high quantum yields. They display similar symmetric emissions with λem at the deep blue region of ∼426u2009nm upon excitation at ∼364u2009nm in DMF, caused by L–L transition of MOBIP+. Existence of [M(mnt)2] n − anions in the solution prolongs the fluorescent lifetimes. For all these compounds in the solid state, the fluorescent emission is blue-shifted and more narrow than that in solution. Based on their crystal structure analysis, the weak stacking interactions in compounds cause the difference of their fluorescence spectrum. Investigations of variable-temperature magnetic susceptibility indicate that 2 has weak antiferromagnetic coupling, while 3b exhibits stronger antiferromagnetic coupling.

Facile assembly of 1D multinuclear Agn (n = 11, 11, 12) alkynyl chains with CF3COO−/CH3COO− as the auxiliary ligand

Three 1D multinuclear silver(I) alkynyl compounds, [Ag11(CCtBu)6(CF3COO)5(CH3OH)]n (1), [Ag11(CCtBu)7(CH3COO)4]n (2) and [Ag12(CCtBu)7(CF3COO)5·H2O]n (3), constructed from AgCCtBu ligand and CF3COO−/CH3COO− auxiliary ligand, have been obtained by changing the type and source of the auxiliary ligand as well as adjusting the pH value in different solvents. The synthesis of 1–3 indicates that this kind of 1D multinuclear Agn (n = 11, 11, 12) alkynyl chain can be isolated through a facile one-pot process. Among these, an infinitely extended 2D supramolecular network is fabricated from 1D chains of 1 via hydrogen bonds, while 3 crystallizes in the chiral space group P21. In addition, the solid state optical diffuse reflection spectra and luminescence spectra of 1–3 have been obtained. Compound 2 is taken as an example to study the electrochemical behaviour of this kind of compound, and the results indicate that 2-CPE possesses good electrocatalytic activity toward the reduction of nitrite.

9-(2-Chloro-phen-yl)-4a-hy-droxy-3,4,4a,5,6,7,9,9a-octa-hydro-2H-xanthene-1,8-dione.

In the title compound, C19H19ClO4, the dihydropyran ring and the cyclohexane ring adopt a half-chair conformation and a chair conformation, respectively. The cyclohexene ring has an envelope conformation with the central CH2 C atom as the flap. This atom is disordered over two positions [site-occupancy ratio = 0.744u2005(12):0.256u2005(12)] above and below the mean plane formed by the other five atoms. In the crystal, O—H⋯O hydrogen bonds between hydroxy and carbonyl groups link molecules into chains propagating along [001].

1,1′-(Ethane-1,2-di­yl)dipyridinium bis­(1,2-di­cyano­ethene-1,2-di­thiol­ato-κ2S,S′)cuprate(II)

In the title ion-pair complex, (C12H14N2)[Cu(C4N2S2)2], the complex anion exhibits a highly twisted coordination environment around the tetracoordinated CuII atom. The dihedral angles between the 1,2-dicyanoethene-1,2-dithiolato ligands and between the two pyridine rings in the cation are 37.49u2005(3) and 29.18u2005(10)°, respectively. Weak C—H⋯N and C—H⋯S hydrogen bonds link the cations and anions into a three-dimensional network.

CCDC 1544145: Experimental Crystal Structure Determination

Related Article: Fang-Ming Wang, Lei Zhou, William P. Lustig, Zhichao Hu, Jun-Feng Li, Bing-Xiang Hu, Li-Zhuang Chen, Jing Li|2018|Cryst.Growth Des.|18|5166|doi:10.1021/acs.cgd.8b00604

Crystal structures and luminescent properties of a cadmium(II) metal-organic framework based on tri(4-pyridylphenyl)amine

Abstract A luminescent cadmium(II) metal-organic framework, [Cd(tppa)2 (bpdc)2]n (1) (tppau2009=u2009tri(4-pyridylphenyl)amine, bpdc =4,4′-biphenyldicarboxylic acid), has been solvothermally synthesized by using Cd(NO3)2·4H2O and a mixture of tppa and bpdc. Single crystal X-ray analysis reveals that 1 crystallizes in the orthorhombic system and Pbcn space group. Its overall structure is a twofold interpenetrated framework, and it shows a porosity of 31.8% based on a calculation by PLATON and a 4-c type topological network with the point symbol of {6^5.8}. In addition, 1 may be exploited as WLED due to its ability to give off yellow light under ultraviolet excitation. Graphical Abstract

Crystal structure of 10a-hy-droxy-9-(3-nitro-phen-yl)-3,6-diphenyl-3,4,5,6,7,8a,9,10a-octa-hydro-1H-xanthene-1,8(2H)-dione.

The central dihydropyran ring of the compound shows an envelope conformation. In the crystal, O—H⋯O hydrogen bonds link the molecules into supramolecular chains propagating along the a-axis direction.