Preparation Of Silicon-based Composite Catalytic Materials And Their Application In Hydrolysis-reduction Tandem Reactions And FC Acylation

In the past ten years,using silica to support a variety of catalytically active guests to construct silicon-based heterogeneous catalytic materials has become one of the important methods for synthesis of green catalysts.Due to the high stability of silica and easy grafting,the support can realize the recycling and reuse of homogeneous catalysts which are structurally sensitive and/or difficult to separate.This is very conducive to improving the atomic efficiency of the catalyst,improving the tedious post-treatment steps,and reducing the pollution of heavy metals and solvents to the environment.Based on this,this paper constructed two supported silicon-based heterogeneous composite catalysts by post-grafting:a dendritic spherical mesoporous organosilicon（mesitylene Ru Ar DPEN@PMOs）supported by homogeneous diamine/ruthenium（Rh-Ts DPEN）and supported Traditional silica balls of metal-organic nanosheets（m Si O₂@MOLs）.The structure and composition of these two materials were characterized by various characterization methods such as solid-state nuclear magnetism and scanning electron microscopy.Combined with their unique structural characteristics,they deeply explored their hydrolysis-asymmetric hydrogen transfer reduction tandem reactions and Friedel-Crafts Application in acylation reaction.The text can be divided into four parts:The first chapter is the introduction.It introduces the characteristics,research progress and challenges in the field of mesoporous silica-based composite catalysts,and discusses the research progress in the tandem reaction of alkynes to prepare chiral alcohols by hydrolysis-reduction and F-C acylation.Finally,the significance of the topic selection and the progress made in this thesis are explained.The second chapter introduces the use of cheap Lewis acid cobalt oxime catalyst and mesitylene Ru Ar DPEN@PMOs to develop a convenient one-pot conversion of terminal alkynes into chiral alcohols through hydration-asymmetric hydrogen transfer（Hydration-ATH）Strategy.Through this method,a series of chiral alcohols with high yield（up to 95%）and high enantiomeric selectivity（up to 99%ee）were obtained.In addition,the ruthenium/diamine active center is stably immobilized in the PMO channel to improve its recycling rate.In the hydration/ATH one-pot enantioselective tandem reaction,the catalyst can be recycled at least 5 times without losing its catalytic activity.The third chapter describes the use of emerging metal-organic nanosheets and traditional silica materials to construct a core-shell structure of m Si O₂@MOLs.Taking full advantage of the high mass transfer rate,large surface area,and high stability of the nanosheet material,a strong Lewis acid m Si O₂@MOLs catalyst for efficient catalysis of the F-C acylation reaction was made.The metal-organic nanosheets use tetravalent zirconium as the metal node and1,3,5-tris（4-carboxyphenyl）benzene（BTB）as the organic linker to self-assemble and form.The carboxyl functionalized surface is grafted onto the surface through coordination bonds.On the inorganic silica microspheres,a silica-metal organic nanosheet composite material with a unique flower-like morphology is formed.The composite material exhibits a high conversion rate（up to 98%）in the catalytic FC acylation reaction.And the reaction rate.Chapter 4 summarizes and prospects the work of this thesis.