Application Research Of Supported Catalyst In Electrophilic Substitution Of Aromatic Ring

Aromatic chloride is a kind of very important organic chemical intermediate, but in the process of its preparation, it will produce a large amount of low-value by-products. There is important practical significance to adjust the selectivity of chlorination to achieve high yield of target product.In this paper, we try to adjust the selective of chlorination in order to improve ratio of para isomer by combining polymer supported catalyst and cocatalyst.The main work is divided into three parts:(1) Using functional groups which owned polymerization ability on the active methylene of acetylacetone to synthesise polymer carrier, then introducing the transition metal into polymer by using acetyl acetone chelating ability, to prepare various polymer supported catalystes.(2) Combining polymer supported catalyst and cocatalyst to catalyze chlorination experiments of chlorobenzene and toluene, The experimental data show that Para selectivity of chlorination of chlorobenzene and toluene reach respectively 80%,56% when its conversion are 33% and 94% by polymer supported iron catalyst and organosulfur compound; at the same time, polymer supported catalyst was modified, then it was used to optimization of experimental conditions and recycling, reuse.(3) Catalytic mechanism of polymer supported catalyst are analyzed and discussed basing on the experimental dataApplication research of polymer supported catalysts in the selective chlorination of aromatic ring is the first reported, it improves the conversion rate of reactants and selectivity of Para isomer, so it is a promising directional selective catalyst.