| In this paper,using two flexible pyrazole-based ligands and one semi-rigid organic ligand were selected as organic ligands and combined with Anderson-type snions or octamolybdate anions with Co(II)/Ni(II)/Cu(II)ions as the central metal ions.,ten polyoxometalate(POM)-based complexes were designed and successfully synthesized.The crystal structures were characterized by single crystal X-ray diffraction(XRD),powder X-ray diffraction(PXRD)and FT-IR spectra(IR).The electrochemical reduction and oxidation,adsorption of organic dyes and catalytic oxidation of thioether and its derivatives were also studied.1.The using of two different spacer length of flexible pyrazole amide ligand(L1=N,N-bis(3-pyrazolamide)-1,2-ethane,L2=N,N-bis(3-pyrazolamide)-1,2-propane)as organic ligands,classical A-series,B-series Anderson-type anions or[Mo8O26]4-anion as an inorganic building units,finally six metal organic complexes were obtained by adjusting metal ions,POM anions and organic ligands:[Co2(L1)2(Cr Mo6(OH)5O19)(H2O)2](1)[Ni2(L1)2(Al Mo6(OH)5O19)(H2O)2](2)[Co3(L1)2(Te Mo6O24)(H2O)6](3)[Ni3(L1)2(Te Mo6O24)(H2O)6](4)[Ni(L1)(H2O)(?-Mo8O26)0.5](5)[Ni(L2)(H2O)(?-Mo8O26)0.5](6)Isostructural complexes 1 and 2 presented 1D chains constructed from B-series Anderson-type POM anions and metal-organic loops[Co2(L1)2]4+/[Ni2(L1)2]4+1D chains.Complexes 3 and 4 are Isostructural 2D metal-organic layer formed by A-series Anderson-type[Te Mo6O24]6-anion and[Co2(L1)2]4+/[Ni2(L1)2]4+ring.Different from complexes 1 and 2,the bridged oxygen of A-series Anderson-type[Te Mo6O24]6-anion is coordinated,which can be linked with the metal anions to construct the metal-organic complexes in high dimension.Both complexes 5 and 6presented 1D chain structures consisting of[?-Mo8O26]4-anions and metal-organic rings[Ni2(L1)2]4+/[Ni2(L2)2]4+of different sizes.The diverse structures of complexes1-6 indicated that the transition metal ions,the type of POMs and spacer length of organic ligands played a crucial role in the reaction system.Complexes 1-3 showed good electrocatalytic activities for Br O3-,and complex 6showed good electrocatalytic activities for Br O3-,KNO2-,AA and H2O2.Besides,the adsorption behavious of complexes 3-5 for methylene blue(MB)were confirmed.Thesemi-rigidpyrazole-amideligand(H2dpyh=N,N-bis(3-pyrazole-amide)-1,2-hexahydrobenzene)was selected as the organic ligand,the classical A-series,B-series Anderson-type anions or[Mo8O26]4-anions were employed as the inorganic building units under hydrothermal conditions to assemble with the transition metals Cu?and Co?to construct four POM-based metal organic complexes:[Cu8(H2O)6(dpyh)4(?-?-Mo8O26)](?-Mo8O26)8.5H2O(7)H4[Cu8(H2O)10(Cr Mo6(OH)5O19)(dpyh)4]·2(Cr Mo6(OH)5O19)4H2O(8)[Co(H2O)(H2dpyh)(?-Mo8O26)0.5](9)[Co3(H2O)6(H2dpyh)2(Te Mo6O24)](10)Complex 7 is a 1D inorganic chain structure composed of?-?type[Mo8O26]4-anion and metal-organic loops which was obtained by introducing molybdate into the synthesis of metal-organic complexes(MOCs)under hydrothermal conditions.?-?[Mo8O26]4-anion is composed of six octahedral Mo O6building blocks and four square-pyramidal or trigonal-bipyramidal Mo O5units by sharing edges and corners.The?-?[Mo8O26]4-anion is linked with[Cu4(dpyh)2]4+to form a 1D chain.Complex 8is a 1D inorganic chain structure composed of semi-rigid pyriazole-amide ligand H2dpyh and B-series Anderson-type POM Cr Mo6with metal Cu?ions.Each metal-organic ring[Cu4(dpyh)2]4+provided three ligand sites connected with Anderson-type Cr Mo6anions and[Cu4(dpyh)2]4+to result in 1D chain.Complex 9 is a2D layer structure based on[?-Mo8O26]n4n-1D inorganic chain.In complex 9,the adjacent?-Mo8O264-formed a POM-baced 1D chain by sharing edges and corners.The stabile metal-ligand organic ring connected with POM-based 1D chain to form a2D layer.Complex 10 is a 2D laye consisted of A-series Anderson-type anions[Te Mo6O24]6-(Te Mo6),semi-rigid pyrazole-amide ligand and Co?ions.The results showed that the types of metal ions,POM anions and p H in reaction system exhibited an important effect on modifying the final structures.Complexes 7-10 showed obvious adsorption behavious for the cationic dyes gentian violet and methylene blue.Complex 7 has excellent catalytic oxidation of thioanisole and its derivatives with great cyclability.Complexes 8-10 can achieve the catalytic oxidation of thioether and its derivatives within a period of time. |
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