Tianyou Song

Synthesis of mordenite single crystals using two silica sources

Abstract Starting with the batch composition 1 Al 2 O 3 :85 SiO 2 :19 Na 2 O:575 H 2 O, a study was made to determine the effect of various additives and other modifications of the starting composition on the growth of larger mordenite crystals in this system. It was found that synthesis of larger mordenite single crystals requires the use of two silica sources, the addition of an appropriate salt, and higher basicity. Thermogravimetric analysis showed two ranges of weight loss which might be concerned with diffusional restrictions because of the large dimensions of mordenite crystals. MAS n.m.r. indicated that the as-synthesized mordenite should be small port mordenite, and there is no octahedral aluminum in the framework of the products. Results of the dispro-portionation of β-methylnaphthalene over different sizes of mordenite crystals show that the shape selectivity observed in these reactions might be related to diffusional restrictions inside the channels of mordenite.

Indium metal-organic frameworks as high-performance heterogeneous catalysts for the synthesis of amino acid derivatives.

Indium metal-organic frameworks (MOFs) were first used as recyclable heterogeneous Lewis acid catalysts for the synthesis of amino acid derivatives with excellent conversion yields. Moreover, exposed ether groups (Lewis basic sites) on the pore walls of In-MOF 2 could activate trimethylsilyl cyanide, forming hypervalent silicate intermediates, as proven by (29)Si NMR.

Synthesis and structure of a new zirconium phosphate with double-stranded chains

The zirconium phosphate [Zr(HPO4)(PO4)F2] · 1.5H2en was prepared, and its structure was determined by X-ray diffraction analysis.

A porous chiral In-MOF with anionic-type diamond network: synthesis, structure and nitrogen gas adsorption

A novel porous chiral In-MOF InH(D-C10H14O4)2 (1) with a left-handed helical channel assembled from D-(+)-camphoric acid (D-H2Cam), has been prepared under solvothermal conditions. Single-crystal X-ray diffraction analysis reveals that compound 1 crystallizes in the tetragonal space group P43212 (no. 96) with parameters: a = 13.8954 A, b = 13.8954 A, c = 17.7870 A, V = 3434.4(7) A 3, Z = 4. The framework feature of compound 1 is characteristic of four-connected anionic-type diamond net with left-handed chiral channel. Moreover, compound 1 exhibits high surface area.

Polymorphic Ln(III) and BPTC-based porous metal–organic frameworks with visible, NIR photoluminescent and magnetic properties

By reaction of 3,3′,5,5′-biphenyltetracarboxylic acid (H4BPTC) with various lanthanide ions, seven novel three dimensional (3D) lanthanide metal–organic frameworks (MOFs) have been prepared under solvothermal conditions, namely, [Ln3(BPTC)3(H2O)2]·3H3O·4H2O·3DMF (DMF = N,N-dimethylformamide, Ln = Eu (1), Tb (2), Sm (3) Dy (4)), [Nd(BPTC)(H2O)2]·H3O·DMF (5), [Er2(BPTC)(HCOO)3(H2O)2]·(CH3)2NH2 (6), and [Tm12(BPTC)8(HCOO)11(H2O)10]·10DMF·7(CH3)2NH2 (7). Combining different lanthanide ions and diversity of coordination modes of the H4BPTC ligand, the seven compounds display interesting structural characteristics. Of these, compounds 1–4 are isostructural and demonstrate a unique 3D coordination framework containing two types of 1D channel, that is built by the novel trinuclear [Ln3O22] SBUs. Compound 5 can be described as a new 3D open-framework structure with quadrilateral-shaped 1D channels based on [Nd2O16] SBUs. Compound 6 has a new 3D pillar network feature constructed by trapezoidal chains linked by bridging BPTC4− ligands, whilst compound 7 exhibits a 3D network with a number of rare oval-shaped channels along the [101] direction. The H4BPTC ligand exhibits five new coordination modes, which are firstly reported in M-BPTC frameworks. Compounds 1–7 all display their typical emission bands upon irradiation at the ligand band at room temperature. Compounds 1–4 present strong characteristic emissions in the visible region, of which compounds 1 and 2 show millisecond luminescence lifetimes. The NIR photoluminescent of lanthanide MOFs is less well observed, especially for the Tm(III) compounds. Owing to the good sensitization of the H4BPTC ligand, compounds 5–7 display near-infrared region (NIR) emission with microsecond luminescence lifetimes. In addition, compounds 2, 5, 6 and 7 exhibit global antiferromagnetic behaviors, of which compound 5 shows a weak ferromagnetic coupling at 235 K.

Synthesis, crystal structure and characterization of a new layered gallium phosphite Ga(HPO3)F3·(trans-C6N2H16) with left- and right-handed helical chains

A new 2D layered gallium phosphite Ga(HPO3)F3·(trans-C6N2H16) 1, possessing left- and right-handed helical chains, has been solvothermally synthesized in the presence of 1,2-diaminocyclohexane (DACH) as a structure-directing agent. The inorganic framework of compound 1 consists of [Ga2O4F6] dimers and HPO3 groups. The dimers are linked up via HPO3 groups to give rise to left- and right-handed helical chains along the b-axis, further these two types of helical chains are alternately connected, with [Ga2O4F6] dimer units functioning as hinges to form a novel 2D layered network in the bc-plane. Interestingly, although a mixture of cis and trans isomers of DACH are used in the synthesis, only the trans isomer is found to direct the formation of compound 1. Moreover, the chirality of the racemic trans isomers of DACH can be transferred into the inorganic framework by hydrogen-bond. The crystal data are as follow: Ga(HPO3)F3·(trans-C6N2H16); M = 322.91; Monoclinic; P21/c (14); a = 11.2635(5) A; b = 9.8212(5) A; c = 10.1458(3) A; β = 102.981(2)°; Z = 4.

Synthesis and X-ray crystal structure characterization of Zn2(HPO4)3·H3NCH2CH2NH3

A novel framework material, Zn2(HPO4)3·H3NCH2CH2NH3, has been synthesised and its crystal structural determined by single crystal X-ray diffraction.

Synthesis, structures and properties of two carboxylate-bridged coordination polymers with linear and ladder chain motifs

Two cadmium(II) compounds, [Cd(nip)(phen)2] n (1) and [Cd2(nip)2(phen)2] n (2) [nip = 5-nitroisophthalate, phen = 1,10-phenanthroline], have been synthesized under hydro (or solvo) thermal conditions and characterized by single-crystal X-ray diffraction. Compound 1 exhibits a 1-D linear chain structure adopting the coordination mode in which one Cd is coordinated to two phen ligands. The formation of 1 was favored by selecting Cd(phen)2(NO3)2 as metal source in ethanol-water. Compound 2 displays a 1-D ladder-like chain structure featuring di-cadmium units. Both 1 and 2 are further assembled into 3-D supramolecular frameworks through interchain hydrogen bonding.

Recycle adsorption of Cu 2+ on amine-functionalized mesoporous silica monolithic

Abstract3-Aminopropyltriethoxysilane functionalized worm-like mesoporous silica monolithic(WMSM-NH2) was prepared and used as a new regenerable adsorbent for the removal of Cu2+ ions. The analysis results show that the WMSM-NH2 monolithic had a high efficiency value of 99.3% for Cu2+ remediation when the Cu2+ solution was at an initial concentration of 10.32 mg/L. The regeneration study of the WMSM-NH2 monolithic presented that the adsorption efficiency of 89.0% was remained and a mass of 92.0% was left after seven adsorption-desorption cycles were executed. The monolithic material with high resistance to the acid and good mechanical stability can facilitate the operations of adsorption and regeneration of the adsorbent.

catena-Poly[[aqua­dioxidouranium(VI)]-μ3-4,4′-oxydibenzoato]

The title compound, [UO2(C14H8O5)(H2O)]n, is a polymeric UO2 complex bridged by 4,4′-oxydibenzoate ligands. One carboxylate group of the bridging ligand chelates a uranyl cation while the other carboxylate group of the ligand bridges two other two uranyl cations, forming a double-chain polymeric structure. The central UVI atom is seven-coordinated in a distorted UO7 pentagonal-bipyramidal geometry. In the crystal structure, O—H⋯O hydrogen bonding links the polymeric chains into a three-dimensional supramolecular framework. Within the bridging ligand, the two benzene rings are oriented at a dihedral angle of 59.0 (2)°.