33. (CrystEngComm) Organo-Ru supported sandwich-type tungstoarsenates: synthesis, structure and catalytic properties
writer:Rui-Qi Meng, Lin Suo, Guang-Feng Hou, Jing Liang, Li-Hua Bi,* Hao-Long Li, Li-Xin Wu
keywords:Polyoxometalate, Catalysis
source:期刊
specific source:CrystEngComm, 2013,15, 5867-5876.
Issue time:2013年
Five organo-Ru supported sandwich-type 17-tungsto-2-arsenates [{B-α-AsW9O33(OH)}{B-β-AsW8O30(OH)}{M4(OH)2(H2O)2}{(RuC6H6)3}]6?(M = NiII, 1; ZnII, 2; CuII, 3; MnII, 4; CoII, 5) have been synthesized by reacting the salts of the corresponding transitional metals with [(RuC6H6)AsW9O34]7?in sodium acetate solutions at pH 6.0. The synthetic method is different from the previously reported transition metal-derivatives. We instead used the organo-Ru functional lacunary species [(RuC6H6)AsW9O34]7?as the starting material. The salts of 1–5 were characterized by powder XRD, IR spectroscopy and elemental analysis. The structures of 1 and 2 have been solved by single-crystal XRD, comprising a rhomblike (M4O16) group sandwiched between two different lacunary Keggin moieties, [B-α-AsW9O34]9?and [B-β-AsW8O31]9?, leading to the asymmetric sandwich-type frameworks, to which three (RuC6H6) units are grafted via Ru–O–W, Ru–O–M and Ru–O–M(W) bonds. Most importantly, the salts of 1–5 show high catalytic activities towards the oxidation of n-hexadecane with air without any additives and solvents. Comparing with the catalytic activities of the corresponding transition metals salts of [As2W18M4(H2O)2O68]10?(M = NiII, 6; ZnII, 7; CuII, 8; MnII, 9; CoII, 10) and their precursors [AsW9O34]9?(11) and [(RuC6H6)AsW9O34]7?(12), the synergistic effect of Ru and transition metal ions in the compounds leads to the enhanced catalytic properties.
http://pubs.rsc.org/en/content/articlelanding/2013/ce/c3ce00045a