Study On Ruthenium Catalyzed Hydrosilylation Reactions

Organic synthetic chemistry has created a beautiful life for human beings,but it has also brought various problems.The development of efficient organic synthesis methods has become more and more important in scientific and social significance.Traditional organic synthesis often relies on the conversion of functional groups.In recent years,the discovery and application value of transition metal catalysts have led to the development of organic synthesis methodology.Due to the unique structure of organosilicon compounds,it can be applied to many fields,which provide a new way for organic synthesis via C-H bond activation and C-N bond formation.Our research is focus on hydrosilylation reaction,which is a reaction of various organosilicon compounds by adding a silicon hydride to an unsaturated organic compound.Our goal is to use a nitrogen-containing heterocycle as a basic raw material and a transition metal ruthenium as a catalyst to selectively construct C-Si,C-N,and C-X bonds,and to optimize the best reaction conditions by controlled variable method,and then"one-pot"synthesis of functionalized target molecules and organosilicon compounds,the results of these studies will be introduced in five parts.The first chapter described the reductive amination reaction of various nitrogen-containing heterocycles,the method of ruthenium-catalyzed hydrosilylation reaction for C-N bond formation,and the area of transition metal catalyzed C-H bond activation for the construction of C（sp²）-Si bond.Finally,the research purpose,content and research significance of this research topic are introduced.The second chapter discusses the use of transition metal ruthenium as a catalyst to obtain a highly selective tertiary amine product by alkylation of aldehydes with amines,and the synthesis of piperidine derivatives by cyclization of glutaraldehyde.This reaction has a wide range of substrate applicability,mild conditions and high yields.Furthermore,the corresponding tertiary amine compounds could be produced by the control of N-alkylation degree of the reductive amination reaction.The third chapter introduces the use of Ru Cl₃as the ruthenium precursor and resorcinol formaldehyde resin precursor as carbon materials to prepare a new heterogeneous catalyst（Ru-OMC）with highly dispersed ruthenium nanoparticles,which is tested in reductive amination.The catalytic efficiency indicates that it has good catalytic performance,and successfully overcomes the P-πconjugation effect of the space effect between the nitrogen atom and the aromatic ring during the reduction of the tertiary amine,and proves that the catalyst could be repeatedly used 14 times by cyclability experiments,which makes the direct reductive amination process more green.The fourth chapter discusses the ruthenium（II）ortho C-H bond silylation of N-containing heterocycles.This protocol features good functional group tolerance,high regioselectivity,which provides a convenient and practical pathway for the synthesis of versatile organosilane compounds.This catalytic system can be also applied to the silylation of challenging sp³C-H bonds.The fifth chapter discusses the C-H bond silylation reaction of oxazoline as a directing group.Oxazoline is a kind of pharmaceutical organic reagent intermediate,which has high value in the chemical and pharmaceutical industries.Therefore,we have developed a C-Si bond coupling reaction system by using ruthenium catalyst,and we explored the application of proper substrate expansion.Finally,the mechanism of the occurrence of the reaction is explored.