Study On The Synergetic Catalytic Properties Of Cu-Based Metal-Organic Frameworks

Many chemical reactions in nature depend on enzyme system catalysis,and the reactions usually depend on a cofactor which is not covalently bound.Flavin cofactor plays a role in many complex ionic and aromatic interactions.It has been found that the combination of organic and inorganic metal complex catalysts with simple flavin derivatives can realize the oxidation of alcohol,amine and alkylaromatics in the photocatalytic system.The special geometric pores of MOFs(Metal-organic frameworks),combined with the abundant weak sites,can change the dominant conformation of substrate or reaction intermediate state through the "space confinement effect",which provides the possibility to complete the chemical,regional and stereoselectivity that is difficult to achieve under the conventional homogeneous conditions.Through the construction of heterogeneous catalytic system of MOFs and the use of host guest interaction,the distance of each component can be shortened,the interaction in the confined cavity can be avoided,such as self-quenching,self-aggregation and other adverse factors.In addition,due to its excellent physical and chemical properties,Cu-based metal organic frameworks is widely used in the catalytic synthesis of drug molecules such as oxazolidinone.In this paper,a metal organic framework material Cu-TDPAT was constructed,which contains copper nodes of two-wheel pulp and ligands of N-rich amine photosensitive dyes.During this period,Cu-TDPAT was tested and characterized including electrochemistry,ultraviolet,infrared,XRD and CO2 gas adsorption.The inherent physical and chemical properties of MOF materials were explored.Besides,the structure activity relationship between the host and guest was studied.UV-vis effectively captured the intermediate species of CuOOH and RFT-OOH,explored the reaction process and gave the corresponding mechanism.Through the condition control experiment and the substrate expansion experiment,the activity comparison of flavins which have similar structural substances was carried out,which widened the catalytic applicability of RFT/Cu-TDPAT system.In addition,the LMCT(Ligand Metal Charge Transition)process of Cu-TDPAT under the excitation of Xe light source was characterized by EPR,and the trifluoromethyl reagent Togni's Reagent II was activated by the highly active copper intermediate.The oxazolidinone with different substituent groups and pharmacological activity was synthesized from allylamine substrates,which greatly expanded the application of Cu-TDPAT in the fields of photocatalysis and drug molecular synthesis.At the same time,we also studied the catalytic application of HKUST-1.The results show that HKUST-1 can also catalyze the trifluoromethylation of oxazolidinone from allylamine substrates under the condition of thermal driving,and the yield is good,slightly higher than that of Cu-TDPAT,and it is also suitable for different substrates.In the end,we also studied the multivariable MOFs(Multivariate MOFs,MTV-MOFs)materials,synthesized the colorless crystal MOF materials containing copper and zinc bimetallic secondary building units and double ligand components,and looking forward to applying them to the hydrocarbon bond activation.