The Creation Of A New Transition Metal Catalyzed System Leading To Ketene Silyl Etherification And Cycloaddition Reactions

α,β-Unsaturated carbonyl compounds,is a very important synthon in organic synthesis,because it can be applied to construct complex molecules.Recently,the construction of a new catalyct reaction system for ketene compounds is also concerned.Therefore,the development of a new catalytic system for the transformation of enones has been attracted much attentions in recent years.In this paper,on the basis of the development of a novel organosilicone material with semi-interpenetrating network that prepared from the in-situ cross-linked PMHS and graphene in reduction of amides,we have successfully developed an organosilicon-supported nanoplatinum,and investiganted its new application in the catalytic hydrosilylation type reduction reactions.The organosilicon graphene supported platinum catalyst,is demonstrated to be highly effective in the 1,4-hydrosilylation of α,β-unsaturated enones,allowing for the facile synthesis of a variety of otherwise inaccessible and substituted silyl enolates.In addition,with the aid of platinum catalyst residue and TBAF,the one-pot and downstream Michael addition of substituted silyl enolates to alkyl acrylates was also reported in this work.Nitrogen-heterocyclic compounds are important intermediates of drugs,pesticides,dyes and other chemical products,asymmetric catalytic synthesis of heterocyclic compounds is challenging in the field of synthetic chemistry.The 1,3-dipolar[3+2]cycloaddition reaction is an important reaction for the synthesis of nitrogen heterocyclic compounds.Therefore,in the second part of this paper,the silver catalyzed α,β-unsaturated ester with 1,3-dipolar cycloaddition reaction was mainly carried out.After a large number of experiments,we found that a highly diastereo-and enantioselective silver-catalyzed cycloaddition reaction ofα,β-unsaturated esters with azomethine ylide-imine was developed for creating novel chiral pyrrolialkanes and their derivatives by employing DTBM-Segphos as chiral P-ligand respectively.In summary,we have investigated the organosilicone/graphene-supported platinum(Pt@G@Si)-catalyzed 1,4-hydrosilylation and asymmetric silver-catalyzed 1,3-dipolar[3+2]cycloaddition reaction,which provided a facile access to the synthesis of various functional compounds respectively.These results gave useful information for the development of novel catalyst systems in platinum-catalyzed hydrosilylation and silver-catalyzed[3+2]cycloaddition reaction.