Application Of Metal Catalysts Supported By Inorganic Ligands In The Catalytic Conversion Of Alcohols

The catalytic oxidation reaction of alcohol is a very classic and extremely important reaction in organic synthetic chemistry,but this reaction often requires complex organic ligands or nitro radicals as auxiliary catalysts to cooperate with the use of traditional metal catalysts,and even requires the use of some strong oxides,such as manganese dioxide,chromic acid,nitric acid,potassium permanganate,Pfitzner-Moffatt,etc.,act as oxidants to promote the reaction,and these strong oxidants will explode violently when they come into contact with the corresponding organic matter in the reaction.The immeasurable consequences.Therefore,how to improve the efficiency of the reaction more safely,efficiently and environmentally is a topic worthy of our exploration for basic research or industrial production.Based on relevant literature reports and the research work of our group in recent years,we have found that metal catalysts supported by inorganic ligands can be used to promote the oxidation of alcohols.This thesis mainly focuses on the structural design,synthesis preparation and screening of metal catalysts supported by inorganic ligands,as well as catalytic applications.Firstly,by substituting the central atoms of the framework of Anderson-type polyoxometalates,the Anderson-type polyoxometalates（NH₄）₃[Cu Mo₆O₁₈-（OH）₆]and（NH₄）₃[Cr Mo₆O₁₈（OH）₆]with different heteroatom centers were prepared and synthesized.In order to give the catalyst different functional characteristics and make it better suitable for different catalytic systems,on the basis of its parent structure,two Anderson-type polyoxometalates derivatives（NH₄）₃[Cr（OH）₃Mo₆O₁₈（OCH₂）₃CCH₂OH]and（TBA）₃[Fe Mo₆-O₁₈（OH）₃（OCH₂）₃CNH₂].In order to expand the types of catalysts,we also designed the synthesis experiment of rare earth-Anderson-type polyoxometalates.Secondly,through the preliminary screening of the catalyst,we used cheap Copper-POMs（NH₄）₃[Cu Mo₆O₁₈（OH）₆]to catalyze the oxidation of alcohols to produce aldehydes or ketones.We have carried out a series of experiments and investigations on the influence of solvent,temperature,amount of catalyst,additives,and p H value in the system on the oxidation reaction of alcohol.After determining and optimizing the relevant catalytic reaction conditions,we expanded the reaction system with more than 59 alcohol substrates,and studied and speculated the relevant catalytic mechanism.The results show that polyoxometalates are an excellent catalyst with high catalytic activity,excellent stability and durability.Not only the preparation process is simple,the synthetic raw materials are cheap,and the preparation process is green and environmentally friendly.Using it to replace traditional metal or non-metal catalysts for the catalytic oxidation of alcohols,not only the catalytic process is safe and simple,but also has extremely high yield and selectivity,and there are few by-products produced in the catalytic process.This is exactly a new route for environmentally friendly green and efficient catalysis.Compared with the traditional catalytic oxidation reaction of alcohol,this method is more promising to realize industrial application and contribute greater benefits and value to human society.