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The synthesis and characterization of a Keggin-type mono-rhenium(V)-substituted polyoxotungstate are described. The dimethylammonium salt [Me2NH2]4[PW11ReVO40] was obtained as analytically pure homogeneous black-purple crystals by reacting mono-lacunary Keggin polyoxotungstate with [ReIVCl6]2- in water, followed by crystallization from acetone at ca. 5 °C. Single-crystal X-ray structural analysis of [PW11ReVO40]4- revealed a monomeric structure with overall Td symmetry. Characterization of [Me2NH2]4[PW11ReVO40] was also accomplished by elemental analysis, magnetic susceptibility, TG/DTA, FTIR, UV-vis, diffuse reflectance (DR) UV-vis, and solution 31P-NMR spectroscopy. Furthermore, [PW11ReVO40]4- and the Dawson-type dirhenium(V)-oxido-bridged polyoxotungstate [O{ReV(OH)(α2-P2W17O61)}2]14- were supported onto anatase TiO2 surface by the precipitation methods using CsCl and Pt(NH3)4Cl2. With these materials, hydrogen evolution from water in the presence of EDTA⋅2Na (ethylenediamine tetraacetic acid disodium salt) under visible light irradiation (≥400 nm) was achieved.

X-ray crystal studies of (NBu(super n)(sub 4))2(M(C3S5)3) (M = Mo, W) and (Fe(C5Me5)2)(W(C3S5)3), electrochemical and spectroscopic analyses of (M(C3S5)3)2- (M = Mo, W) anion complexes and studies of the electrical conductivities of their oxidized species, revealed a distorted trigonal prismatic coordination near the metal atom. (NBun4)x(M(C3S5)3) resulted from the reaction of these complexes with iodine, (Fe(C5H5)2)(PF6) and (TTF)3(BF4)2.

We report the synthesis of a novel porphyrin-based metal carboxylate framework, [Cu2(ZnBBCPPP)(H2O)2]•6DMF• 11H2O (BBCPPP-Cu2), with a large void volume, by using a two-dimensionally expanded building block: {bis[3,5-bis(4-carboxyphenyl)phenyl]porphyrinato}zinc (ZnBBCPPP). Singlecrystal X-ray analysis of BBCPPP-Cu2 revealed a threedimensional network. The void volume per unit cell of BBCPPP-Cu2 is 76.8%, which is considerably larger than that of previously reported porphyrin-based MOFs. [ABSTRACT FROM AUTHOR]

We successfully synthesized a novel porphyrin-based metal carboxylate framework, [Cu2(ZnBDCBPP)]·5DMF&· 5H2O, with expanded pore windows and interior spaces, by using a ZnBDCBPP building block. Single-crystal X-ray analysis revealed that the framework of [Cu2(ZnBDCBPP)] formed a three-dimensional network. The cavity was surrounded by a total of 16 accessible metal sites with two distinct metals, and large pore windows were present. These large pore windows appear to be crucial for an enhanced catalytic performance because they facilitate the diffusion of substrates and products. [ABSTRACT FROM AUTHOR]