Studies On Transition Metal Catalyzed Cycloaddition Reaction Of Diazo Compounds

Nitrogen-containing heterocyclic skeletons are widely distributed in functional organic compounds and are also an important class of synthetic intermediates.With the rapid development of the fields of medicine,pesticides and organic functional materials,there is an increasing demand for the types and quantities of nitrogen-containing heterocyclic compounds.Therefore,the development of efficient synthetic methods to construct nitrogen-containing heterocyclic skeletons will be of significance and urgence.Herein,we discussed transition-metal catalyzed cycloaddition reaction of diazo compound to highly efficient and regioselective construct a series of highly functionalized nitrogen-containing heterocyclic skeletons,such as indolizine derivatives,1,4-oxazepine compounds and 3-azacyclo[m.2.0]compounds.There are four parts for this dissertation:Chapter 1 is the brief review of relevant lireratures,including diazo compound;diazo-carbene;ylide cycloaddition reaction and copper catalyzed cross-coupling reaction of diazo compounds with terminal alkynes.At the end of this chapter is a short introduction of research contents of this dissertation.In chapter 2,we have reported Rh2?OPiv?4-catalyzed regiodivergent[3+2]or[5+2]cycloaddition reaction of alkynes and quinoline ylide intermediates generated from quinoline and donor-acceptor diazo compounds to highly efficient construct five-membered indolizine derivatives and seven-membered 1,4-oxazepine compounds,respectively.Mechanistic investigations reveal that the[3+2]cycloadditions may proceed through a metal-assisted 1,3-ester migration process.In chapter 3,we have realized an unprecedented Cu?PPh3?3Br-catalyzed tandem cross-coupling/[2+2]cycloaddition reaction of 1,6-allenynes with diazo compounds to highly chemo-and regio-selective provide a varieties of highly functionalized 3-azabicyclo[5.2.0]frameworks.Moreover,the target products readily transform to functionalized quinolines via oxidative radical rearrangement under heating condition,which proves that these compounds have good prospects for transformation and application.In chapter 4,we have developed a novel and general Cu?PPh₃?₃Br-catalyzed tandem cross-coupling/[2+2]cycloaddition reaction of 1,n-allenynes?n=6,7?with diazo compounds to highly efficient and selective construct a series of highly functionalized 3-azabicyclo[m.2.0]compounds?m=5,6?.Mechanistic investigations reveal that the reaction proceeds through intermolecular cross-coupling to form bisallene intermediates,followed by subsequent intramolecular[2+2]cycloaddition.