Study On The Design And Catalytic System Of Green Alkene Oxidation Catalytic Materials

The Wacker catalytic oxidation reaction is a reaction in which an olefin compound is oxidized to aldosterone under the action of palladium catalyst.The classical Wacker reaction takes Pd Cl2/ Cu Cl2 as the catalytic system.When applied to olefin with high carbon number and cyclic olefin,the catalytic performance varies greatly.At the same time,the reaction system has great disadvantages,such as metal pollution,the presence of chlorine by-products,catalyst separation difficulties.For homogeneous catalyst is highly active and selective,at the same time,considering the limitations of difficult to recycle,is to improve the catalyst,the introduction of inorganic mesoporous materials and the corresponding organic ligands,metal ligand design developed the load as well as a way of using the organic ligand metal of high catalytic activity and can use the properties of inorganic mesoporous materials separation recycling of the catalyst,develop green highly active and can be repeatedly used a new type of catalyst become the new direction.Mesoporous molecular sieves have unique structural properties and abundant silicon hydroxyl groups on their surface,so they can be grafted with ligands of different properties to form catalysts with different catalytic activities under metal coordination load.In this paper,on the premise of mesoporous materials,grafted ketone ligands were modified,and finally,heterogeneous catalysts with high catalytic properties and recyclable properties were prepared by palladium supported on metal ligands.The main research contents are as follows:(1)Through the SBA-15 modified mesoporous materials,reaction introducing thiophene ligands,and then,by using the method of metal ligand to palladium(II)the load to the mesoporous material carrier,heterogeneous palladium catalyst is prepared,at the same time will be the catalyst used in preparation of cyclohexene oxidation reaction of cyclohexanone,using hydrogen peroxide as a single antioxidant,explore the catalytic activity of the catalyst and the optimum process conditions of reaction?(2)In thiophene ligands have good catalytic effect under the premise of independent synthetic more symmetrical structure of the ligand double nitrogen fluorenone,has better coordination effect to the metal palladium,grafted mesoporous materials,the preparation of a better load type catalyst,the reaction system is optimized,using hydrogen peroxide as a single oxidant instead of the traditionalWacker reaction Cu Cl2,catalyst showed good catalytic activity and can be recycled many times,explore the suitable reaction conditions,in acetonitrile as the solvent,olefins and the amount of catalyst in 200:1,olefins and the amount of acid additives in50:1,the quantity of olefins with hydrogen peroxide in 4:1,Under the condition that the reaction temperature was controlled at 60°Cand the reaction time was 4h,the conversion rate of cyclohexene was 89.5% and the yield of cyclohexanone was75.3%.