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1.
1 INTRODUCTION The contemporary studies on POMs reveal theirspecial properties which endow these materials withwide range of applications, such as catalysis, medi-cine[1], material science[2], etc. Current research inte-rest mainly focuses on the development of solid ma-terials with unusual structural complexity and con-comitant diversity of applicable properties. A series ofmolybdate oxide phases have been synthesized, inwhich the polymolybdate anions are linked intoinfinite 1-, 2- or 3…  相似文献   
2.
1INTRODUCTIONPolyoxometallates(POM)areofgreatinterestnotonlyfortheirstructuralvarietybutalsotheirunexpectedproperties[1,2].Theseinorganicanionshavebeenwidelyinvestigatedasdiversascatalysis,biology,medicine,magnetochemistryandmaterialscience[3~7].Thestudiesonthecoordinatedpoly-oxometallateswithorganicligandsmighthelptounderstandtherolesofpolyoxometallatesoncatalysis.Todate,aseriesofoctamolybdateswhichcanbedescribedas[Mo8O26X2]2n-4(nisthenormalchargeofthecoordinatedbaseX)havebeenreport…  相似文献   
3.
镧钼钒磷杂多配合物催化乙苯选择性氧化制苯乙酮   总被引:10,自引:0,他引:10  
苯乙酮是重要的化工原料 ,工业上多采用苯与乙酰氯在三氯化铝存在下合成。苯与乙酰氯在三氯化铝存在下反应后生成强酸 ,易造成对生产设备的腐蚀和环境的污染。低浓度的过氧化氢价廉易得 ,其反应产物为氧气和水 ,对生产设备和环境不会造成影响。因此由乙苯与过氧化氢在常压下选择性氧化制苯乙酮有较高的实际应用价值 ,满足可持续发展的要求 [1] 。杂多化合物可作为酸性 ,氧化还原等多功能的催化剂 ,可在分子水平上对其酸性及氧化性进行调变。杂多化合物应用于催化许多有机合成反应 ,具有广阔的应用前景 [2 ] 。将稀土引入杂多阴离子中 ,由于…  相似文献   
4.
镱钼钒磷四元杂多化合物催化苯酚羟化反应的研究   总被引:3,自引:0,他引:3  
合成了具有Keggin结构镱钼钒磷杂多化合物 ,用IR、UV、XRD、ICP等手段对其结构进行了表征。并研究了该杂多化合物对苯酚过氧化氢羟化反应的催化活性。实验结果表明 :以甲醇为溶剂 ,用镱钼钒磷杂多化合物为催化剂 ,当n(phOH)∶n(H2 O2 ) =1∶2 ,反应体系的pH =5.0 ,反应时间 4h ,苯酚转化率为 4 1 66% ,对苯二酚产率可达到 4 0 .2 4 %。  相似文献   
5.
1 INTRODUCTION Schiff base ligands have been studied for a longtime due to the instant and enduring popularity fromtheir easy synthesis and versatility complexes. Theyplay an important role in the development of coor-dination chemistry as well as inorganic biochemistry,catalysis, optical materials and so on[1, . Consider- 2]able attention has been focused on the syntheses andstructures of copper(II) and nickle(II) complexes.The nickel complexes with multidentate Schiff baseligands have …  相似文献   
6.
1INTRODUCTIONThepolyoxomolybdateshavebeenwidelyresearchedinmanyfieldssuchascatalysis,biology,medicineandmaterialsciencebecauseoftheirrichphysicalandchemicalproperties[1].Thoughmanypolyoxomolybdateshavebeenreported[2],furtherresearchisstillnecessaryforthestudyof搑eduction-oxidation-reconstitution?self-assemblyprocesses[3,4].Polyoxomolybdatesarenormallybuiltupundersuitableconditionsbyafewbuildingblockssuchas{Mo2},{Mo8}and{Mo9}inself-assemblyway[5,6].The{Mo18}clustershaveseveralstructuralty…  相似文献   
7.
1 INTRODUCTION Polyoxometallates are of great interest not only for their structural variety but also for their un- expected properties[1, 2]. These inorganic anions had been widely investigated in catalysis, biology, me- dicine, magnetochemistry and materials science[3~6]. Especially, the studies on the organic ligands coor- dinated by polyoxometallates might help to under- stand the catalytic mechanism of polyoxometallates. In recent years, several octamolybdates containing organic l…  相似文献   
8.
A binuclear vanadium complex NH4[(VO)22-O)(nta)2][Eu(H2O)9] was synthesized by reaction of NH3VO3, nitrilotriacetic acid and EuCl3 in one aqueous solution. The crystal X-ray analysis shows that the complex contains one binuclear vanadium anion [(VO)22-O)(nta)2]4- and one [Eu(H2O)9]3+ cation. The molecules are built up to a three-dimensional supramolecular structure through hydrogen bonding. CCDC: 238716.  相似文献   
9.
1 INTRODUCTION The polyoxometalates have aroused extensive in-terest due to their alluring topologies and potentialapplications in various fields (e.g. catalysis, biology,medicine and materials science)[1]. A variety of po-lyoxometalate anions and related fragments withoxygen-rich compositions can serve as inorganic li-gands to coordinate secondary transition metal ions(so-called heterometals, such as Cu2 , Ni2 , Co2 andMn2 )[2]. Thus, larger discrete species and infinitelyextending ar…  相似文献   
10.
The crystals of the title compounds (H3O)(C3H5N2)[Mn(OH)6Mo6O18]·3.5H2O 1 and (H3O)3[Co(OH)6Mo6O18]·7H2O 2 have been prepared and structurally determined by X-ray single-crystal diffraction. Compound 1 crystallizes in monoclinic, space group C2/c with a = 21.5018(9), b = 10.9331(5), c = 11.8667(5)A,β = 95.3570(10)o, V = 2777.5(2)A3, Z = 4, Dc = 2.802 g/cm3, Mr = 1171.80,μ(MoKα) = 3.173 mm-1, F(000) = 223, the final R = 0.0458 and wR = 0.1041 for 2093 observed reflections (I>2σ(I)); Compound 2 crystallizes in monoclinic, space group P21/c with a = 11.4042(12), b = 10.9481(11), c = 11.6722(12)A, β= 99.948(2)o, V = 1435.4(3)A3, Z = 2, Dc = 2.794 g/cm3, Mr = 1207.80,μ(MoKα) = 3.223 mm-1, F(000) = 1160, the final R = 0.0544 and wR = 0.1066 for 1906 observed reflections (I > 2σ(I)). Both compounds 1 and 2 adopt the Anderson structure, in which the anion is of centrosymmetry and formed by six octahedral edge-sharing MoO6 units surrounding the central MO6 (M = Mn or Co) octahedron.  相似文献   
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