Syntheses And Catalytic Properties Of Metal-Organic Frameworks Constructed From Resorcin[4]arene Ligands

Metal-organic frameworks?MOFs?,as a new class of porous material,havebeen applied in many research fields.The introdiction of polyoxometalates?POMs?into MOFs can preparenovel structure with excellent properties.In this thesis,three MOFs were constructed by two kinds of resorcin[4]arene ligands under solvothermal conditions.These three different structures all have catalytic activity sites,two of which also contain POMs.According to their respective characteristics,the catalytic performance and luminescence properties were studied,respectively.Astablemicroporousanionicmetal-organicframework?MOF?,[?CH₃?₂NH₂]₆[Cd₃?L-1??H₂O?₂]·12H₂O?1?,has been synthesized via solvothermal assembly of a new resorcin[4]arene-functionalized dodeca-carboxylic acid(H₁₂L-1)and Cd?II?cations.1 exhibits a fascinating 3D microporous framework structure,in which water molecules and the[?CH₃?₂NH₂]⁺cations were located.Remarkably,the exposed Lewis acid Cd?II?sites of activated 1 make it an efficient heterogeneous catalyst for the cycloaddtion of CO₂ with epoxides at 1 atm and 20 atm,respectively.Importantly,the activated samples of 1 can be reused at least five circles with the excellent catalytic performance.Moreover,the fluorescent detection of Cr₂O₇^2-and Fe³⁺was studied by using 1 as a potential luminescent sensor.We synthesized a new polyoxovanadate-resorcin[4]arene-based metal-organic framework?POMOF?,[Co₂?L-2?_0.5V₄O₁₂]·3DMF·5H₂O?1?,assembled with a newly functionalized wheel-like resorcin[4]arene ligand?L-2?.1 features an elegant porous motifandrepresents a rare example of POMOFs composed of both resorcin[4]arene ligand and polyoxovanadate.Remarkably,1 shows open V sites in the channel,which makes 1 an efficient heterogeneous Lewis acid catalyst for cycloaddition of CO₂ to epoxides with high conversion and selectivity.Strikingly,1 also exhibits high catalytic activity for the heterogeneous oxidative desulfurization of sulfides.Particularly,the heterogeneous catalyst 1 can be easily separated and reused with good catalytic activity.A new highly stable copper?I?-based metal-organic framework?MOF?,namely,[Cu₄^I(SiW₁₂O₄₀)?L-2?]·6H₂O·2DMF?1?,was synthesized by incorporating Keggin-type polyoxometalate?POM?anions and a functionalized wheel-like resorcin[4]arene-based ligand?L-2?under sovothermal condition.1 exhibits a charming 3D supramolecular architecture sandwiched by the POM anions.Noticeably,1 is exceptional chemical stability,especially in organic solvents or aqueous solutions with a wide range of pH values.Considering the catalytically active Cu?I?sites in 1,the azide-alkyne cycloaddition?AAC?reaction was studied by employing 1 as the heterogeneous catalyst.Most strikingly,1 exhibits excellent catalytic activity as well as recyclability for the AAC reaction.