| The design and synthesis of chiral polyoxometalates （POMs）, which may incorporatefunctionality from both POMs and chiral materials, recently have attracted considerablyattentions. Its unique soluble metal-oxygen structure provides an ideal model for the study ofchirality origin and chiral transfer. And its high electronegativity, adjustable acidity, redoxactivity and nanometer size, brings new hopes to design and synthesize of the more versatilenonlinear optics, stereoselective catalysis, medicine and another new materials. In this paper,we have synthesized a series of chiral polyoxometalates from three different approachesbased on the point of molecular design, self-assembly, self recognition and surfacemodification. Through the discussions of the synthesis, structures and properties of thesecompounds, we have found some important references for the study of chiral origin andspontaneous resolution.With a conventional synthesis procedure, twenty-three chiral POMs have beensynthesized, and characterized by element analysis, IR, UV-Vis, TG, CD spectra, NMR andsingle-crystal X-ray analysis. And some of thermal stabilities, solution stabilities, nonlinearoptics, liquid crystals, Gasochromic, photochromic and catalytic properties of the compoundshave been partially investigated.1. With the “self assembly†synthesis strategy, we have synthesized nine organic-functionalized hybrid polyoxometalates by the reaction of flexible multidentate ligands suchas organic bisphosphonate and EDTA in the absence of chiral source. Experimental resultsshow that these compounds have important potential application prospects in liquid crystals,nonlinear optics, catalysis and other fields.Na5（NH4）{VIV[（Mo2O6）CH3C（O）（PO5）2]2}·13H2O （1）（NH4）4{VIV[（Mo2O6）NH3CH2CH2CH2C（O）（PO5）2]2}·6H2O （2）（NH4）8{Mo2VO4[(MoVI2O6)CH3C（O）（PO5）2]2}·14H2O （3）L,D-（NH4）6{Mo2VO4[(MoVI2O6)NH3CH2CH2CH2C（O）（PO5）2]2}·10H2O （4）Na6{Mo2O5[（Mo2O6）NH3CH2CH2CH2C（O）（PO5）2]2}·20H2O （5）Na1.5（CH5N）4.5{Mo2O5[（Mo2O6）NH3CH2CH2C（O）（PO5）2]2}·7.5H2O （6）（NH4）8{MoO2[（Mo2O6）NH3CH2CH2CH2C（O）（PO5）2]}4·2H2O （7）（NH4）2[Mo2O4（EDTA）]·2H2O （8）[Mn（H2O）6][Mo2O4（EDTA）]·5H2O （9）2. Based on the “building blocks†synthetic approaches, we have used theWaugh-type polyoxoanion [MnMo9O32]6-as the basic building block to react withdifferent transition metal cations, imidazole and rare earth ions. Herein thirteen multidimensional chiral POM-based compounds have been synthesized. From thestructure analyses of these compounds, it provide a series good theoretical and practicalmodels for the studies of the spontaneous resolutio, chiral recognition and chiral transfersof chiral POMs in the solid state. And experimental results show that this class of chiralcompounds are kind of potential excellent photocatalysts and gaschromic materials.L,D-（Zn（H2O）3）3[MnMo9O32]·4H2O （10）（Himi）6[MnMo9O32]（11）Na2（Himi）4[MnMo9O32]·2H2O （12）Na3（Himi）3[MnMo9O32]（13）L,D-NH4Mn2.5[MnMo9O32]·11H2O （14）Na4Mn[MnMo9O32]·11.5H2O （15）KNa3Mn[MnMo9O32]·9H2O （16）Na2Ni2[MnMo9O32]·12H2O （17）L,D-Mn3[MnMo9O32]·13H2O （18）L-Ni3[MnMo9O32]·11.5H2O （19）Co3[MnMo9O32]·15H2O （20）Cu3[MnMo9O32]·15H2O （21）[（CH3）4N]2Nd[HMnMo9O32]·6H2O （22）3. Based on the principles of organocatalyts, we have grafted the optically puretrans-（1R,2R）-diaminocyclohexane onto the polyoxoanion successfully by the Si-basedanchor. A new optically pure trans-（1R,2R）-diaminocyclohexane grafted polyoxometalatehas been synthesized, which shows excellent asymmetric catalytic activity and goodenantioselectivity for the direct Aldol reactions, and can be easily recycled.[（C4H9）4N]3{PW11O39O[Si（CH2）3-（1R,2R）-NHC6H10NH2]2}·3DMF （23）... |
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