Synthesis And Application Of Exine-driven Symmetric Tetramethyl Six-membered Cucurbit-based Frameworks

TMeQ[6]is a cucurbitural symmetric tetramethyl-substituted Q[6]and We mainly studied TMeQ[6]-based supramolecular frameworks assembled through outer surface interactions and different TMeQ[6]-basedframeworks constructed by self-induction or metal ion induction under different acids and different concentrations of the same acid and their properties.On the one hand,three self-induced frame structures of cucurbitural were formed under the conditions of 1-2 M H₂SO₄,3-4 M H₂SO₄and 5-6 M H₂SO₄（named A,B and C,respectively）and different dyes were adsorbed on these frame materials to form solid fluorescent materials（named FDS）.Firstly,the feasibility of mass preparation of TMeQ[6]frames in different sulfuric acid solution concentrations and the stability of frame materials were investigated by using X-ray single crystal diffraction technology,nuclear magnetic resonance technology,thermogravimetric analysis technology and X-ray powder diffraction technology.The fluorescence properties of the frame materials were investigated by UV-Vis absorption spectroscopy and fluorescence spectroscopy.The fluorescence of these solid fluorescent materials was enhanced or quenched to different degrees compared with the fluorescence of the original dyes.Among them,frame material B based on TMeQ[6]adsorbed sulfur T to form a fluorescent probe material,which has a specific response to formaldehyde gas,and can form a solid fluorescent probe aimed at detecting formaldehyde.A framework material B based on TMeQ[6]adsorbed methylnaphthol to form a solid fluorescent material with a specific response to benzene,which can be prepared as a fluorescent probe material for detection of benzene.The application of solid fluorescent materials in selective adsorption of volatile organic gases（VOCs）and selective adsorption of alkanes was also explored.On the other hand,TMeQ[6]/[Pd Cl₄]^2-frame material is captured in 4M HCl and released in 1M HNO₃.The screening of coordination anions of several metal ions and the metal ions of[Pd Cl₄]^2-in 4M HCl were investigated by single crystal diffraction,X-ray powder diffraction and energy spectrum techniques,which provided a direction for the recycling of metal and metal ions in frame materials.