Study On Rhodium Catalyzed C-H Activation Methodology And Its Application In Polymerization

In recent years,the Rh(?)catalyzed C-H activation reactions has become a mild,efficient and atom-economic method for the synthesis of functional compounds.More and more reactions have been developed due to the concern of chemistry researchers.This dissertation mainly focuses on the reaction patterns of coupling reagents in Rh(?)catalyzed C-H activation reactions and utilizes mild and diversely reactive diazo coupling reagents to develop novel C-H activation reactions.Meanwhile,a study on applying the C-H activation strategy to polymer synthetic methodology is also conducted.The main contents include:The first chapter briefly reviews the coupling reagents used in Rh(?)catalyzed C-H activation reactions recently,including alkynes,alkenes,diazo compounds,etc.Each reagent is classified for detailed introduction by the number,type and pattern of reactive function groups.Finally,the examples of polymer synthesis based on C-H activation are analyzed.In the second chapter,a Rh(?)-catalyzed-C-H-activation-based intermolecular annulation reaction between phenyl hydrazines and a-diazo-?-ketoesters for the synthesis of l,4-dihydrocinnolines is reported.A substrate replacement technique is applied in the optimization of reaction conditions and a more compatible reaction condition is obtained.High regioselectivity is found in substrate scope expansion.According to the results of H-D exchange experiments and the kinetie isotope competition experiments,a meehanism eonsisting of successive C-H activation and intermolecular dehydration is proposed.A high-yield amplification,which provides gram-scaled products,Proves the application value of this reaction.The third chapter reports a simple and efficient synthetic strategy for 4-hydroxyl-1-naphthoates by the coupling of phenyl enaminones and 2-diazo-2-dialkoxylphosphonyl acetates,and a successive ring-closure condensation with TBAF.These two reactions are both compatible with various substituents and provide high yields with different substrates.The second reaction is proved to experience a phosphonate group leaving proeess before the nucleophilic reaction by control experiments,which provides a novel thinking of the application of phosphonates.Moreover,this method avoids the use of strong base for ring closure and has a mild reaction condition,which promises the synthetic application.In the last chapter,a polymerization method based on N-nitroso directing phenyl olefination is reported.Two monomers are designed and synthesized.Two polymerization products are obtained under proper reaction conditions.Through optimization of the reaction conditions,the PDIs of the polymers are reduced.Further transformations by nitroso group removal are realized and two polymers bearing amino group are gained.This method firstly introduces Rh(?)catalyzed C-H bond olefination into polymerization and narrows the molecular weight distribution of the polymer generated by C-H activation reaction,thus expand the application of C-H activation in polymerization methodology.