Evans-Showell-Type Polyoxometalates Constructing High Dimensional Inorganic Organic Hybrid Compounds with Copper Organic Coordination Complexes: Synthesis and Oxidation Catalysis

摘要

Four new hybrid architectures containing a [Co2Mo10H4O33](6-) polyoxoanion, (en)[Cu-3(ptz)(4)(H2O)(4)][Co2Mo10H4O38].24H(2)O (1), (Hbim)(2)[{Cu-(bim) (2) (H2O) (2) }(2) {CO2Mo10H4O38}].5H(2)O (2), H-2[Cu(dpdo)(3) (H2O)(4)] [{cu(2)(dpdo)(3)(H2O)(4)(CH3CN)}(2){CO2Mo10H4O38}(2)].9H(2)O (3), and (H(2)bpp)(4)[{cu(H2O)(2)}{Naco(2)mo(10)H(4)O(38)}(2)].10H(2)O (4), where ptz = 5-(4-pyridyl)-1H-tetrazole, en = ethylenediamine, bim = benzimidazole, dpdo = 4,4'bipyridine-N,N'-dioxide, and bpp = 1,3-bis(4-pyridyl)propane, have been prepared and characterized through elemental analysis, thermogravimetric analysis, IR spectroscopy, and powder and single-crystal X-ray diffraction. Compound 1 shows a 3D host-guest framework composed of 3D Cu-ptz as the host and Evans-Showell-type polyoxoanion [Co2Mo10H4O38](6-) as the guest. Compound 2 is constructed from [Co2Mo10H4O38](6-) polyoxoanions and Cu-bim coordination complexes to form a 2D covalent layer. Compound 3 also exhibits a 2D hybrid network based on [Co2Mo10H4O38](6-) polyoxoanions linked by Cu-dpdo coordination groups. Compound 4 is a 1D double chain structure composed of [Co2Mo10H4O38](6-) polyoxoanions joined together by Na+ and Cu2+ cations. As far as we know, compound 1 is the first host-guest compound with an Evans-Showell-type polyoxometalate as the guest, and compounds 2 and 3 are the first 2D inorganic-organic hybrid architectures constructed from Evans-Showell-type polyoxometalates. Compounds 1-4 are redox catalysts that heterogeneously prompt sulfide and alcohol oxidation with excellent efficiency.