Preparation Of Mesoporous Nanosphere-supported Palladium Catalyst And Study On Its Catalytic Performance For Coupled Hydrolysis

With the development of green chemistry,the construction of highly stable heterogeneous catalysts superior to ordinary homogeneous catalysis has been explored by scientific researchers because of its simple separation and recyclability.With the deepening of research,researchers put forward higher requirements for heterogeneous catalytic reaction:whether noble metal catalysts and their ligands can be built on recyclable heterogeneous supports without affecting their catalytic activity.In this paper,the construction of two types of heterogeneous catalysts was studied:（1）The first type uses TEOS（tetraethyl orthosilicate）as silicon source and CTAB（cetyltrimethylammonium bromide）as template.After etching and removing the template,Al（O-i-Pr）₃（aluminum isopropoxide）is adsorbed in aqueous solution,and finally Pd Cl₂（palladium chloride）is adsorbed on catalytic carrier 2 under negative pressure,A bimetallic supported mesoporous solid acid palladium material Cat 3 was obtained by modifying the pores with pore size reduction,and it was applied to the hydrolysis and oxidation of Diphenylacetylene.The results show that the prepared bimetallic supported mesoporous solid acid palladium material has excellent catalytic activity and stability,The obtained benzoyl obtained a high yield（94%）.In the subsequent recycling,it was found that the catalytic activity of the heterogeneous catalyst did not change significantly,and the yield of benzoyl did not change greatly during the six times of recycling of the bimetallic supported mesoporous solid acid palladium material.（2）The second type is to successfully prepare a kind of flower spherical mesoporous nanoparticles with tea（triethanolamine）,nasal（sodium salicylate）and CTAB（cetyltrimethylammonium bromide）as templates and TEOS（tetraethyl orthosilicate）,btee（N-benzoyl-L-tyrosine ethyl ester）and（ETO）₃sipph₂（2-（diphenylhydroxyphosphinyl）ethoxysilane）as silicon sources DMOSNs@PPh₂@Pd（OAc）₂,The Sonogashira coupling reaction of aniline and phenylacetylene was successfully catalyzed.The coupling yield of Diphenylacetylene（90%）achieved good results,and can be successfully applied to the coupling hydrolysis of aniline and phenylacetylene in one pot in series.Then we applied heterogeneous catalyst through circulation DMOSNs@PPh₂@Pd（OAc）₂ proved that the catalyst can be recycled for more than five times,and the catalytic activity and stability have not changed significantly.