Study On The Efficient Construction Of The Polycyclic Structures Via Intramolecular Metal Carbene Cascade Reactions

Polycyclic compounds,especially heter-polycycles,is an important chemical substance,which is widely distributed in b ioactive molecular and pharmaceuticals;and also show applications in pesticide,spice,materials and etc.Wherease,it is a great chal lenge to synthesize polycycles via general and efficient methods.In the recent years,our group has developed a carbene cascade reaction based on diazo compounds as carbene precursor,which was initiated via a metal-catalyzed metal carbene formation followed by reacting with a alkynyl group to generate another metal carbene on one of the alkynyl carbon,and terminate the cascade process with typical carbene reaction.The process shows high bond formation efficiency,and provide an effective synthetic methodology for the direct construction of polycyclic compounds.In the chapter 1,introduction of metal carbene,diazo compounds,enyone and the related background are presented.In the chapter 2,we have disclosed a copper-catalyzed cascade reaction of alkyne-tethered diazo compounds,which provides a practical and effective access to multisubstituted 4-carboxyl quinoline derivatives.We also investigated the reaction mechanism and presnted the synthetic utility of the current method.In the chapter 3,we have developed a Pd-catalyzed carbene/alkyne metathesis approach: A direct access to the polycyclic compounds,and the obtained prodcuts could be transformed into endocyclic compounds via a formal [4+2] cycloaddition.