Radical-Mediated Difunctionalization Of Alkenes

Olefins are a kind of basic chemical raw materials containing carbon-carbon double bond functional groups.The diversity transformation of olefins offers a strong guarantee for the manufacture of polymer material and fine chemicals.Therefore,the exploration and development of novel,efficient and green olefin efficient conversion methods has positive and profound significance for synthesis chemical.Among these methods of alkenes transformation,the 1,2-difunctionalization of olefins realizes the sequential introduction of two molecular fragments by opening the?bond of olefins and constructing new C-C bond or C-X bond.Naturally,this strategy has become an important means for olefin high value-added conversion,and also provides an efficient and convenient route for the synthesis of structurally diverse organic molecules.In recent years,radical mediated difunctionalization of olefins has attracted more and more attention because of its high atom-and step-economy,which not only provides a new and unconventional strategy for forging of C-C or C-X bond,but also provides complementary reactivity and selectivity for traditional organometallic-or ionic-type reactions.Considering the great synthetic potential and application prospect of this radical strategy,the novel radical-mediated 1,2-bifunctionalization reaction of olefins have been explored by utilizing single electron transfer(SET)under mild conditions.These reactions investigated new construction methods of C-C,C-N,C-O and C-S bond,and synthesized a series of O-,N-and S-containing cyclic and acyclic molecules with important skeleton and potential biological activities.Meanwhile,these reactions provided new ideas and protocol to the green and efficient conversion of olefins.This paper is divided into the following five chapters:Chapter 1:Firstly,this chapter sketches the briefly history of radical chemistry,and summarizes the radical types,radical initiation methods and radical reaction models.Then,the basic rules of the reaction between radicals and olefins were summarized.Finally,the oxysulfurization,carboamination and dicarbofunctionalization reaction of alkenes are briefly summarized.Chapter 2:The oxysulfurization and oxysulfoxidation of olefins of unsaturated ketoximes with disulfides has been developed by using Di-t-butyl peroxide(DTBP)or Na IO₄ as oxidant under copper-catalyzed conditions via radical cascade reaction.A series of sulfoxide and thioether group-containing isoxazolines were efficient synthesized by this protocol.This method provides a case for the selective synthesis of organic sulfides with different valence states.Chapter 3:The carboamination of internal unactivated olefins of unsaturated oxime ether with Togni's reagent II or fluoroalkyl iodides has been developed under mild conditions via radical-mediated amino shift reaction derived from the EDA complexes.Based on this radical-mediated amino shift reaction derived from the EDA complexes,a series of fluoroalkyl-containing aminoketone derivatives were synthesized for the first time.Significantly,besides fluoroalkyl radical precursor,this method is also compatible with some well-established EDA acceptors to give various functionalized aminoketones.Subsequently,the reaction intermediates and transition states in the transformation were deeply explored and a proposed mechanism was given by control experiment,physical organic and computational chemistry.The reactions described in this chapter will provide a reference model for the difunctionalization of unactivated olefins through distal radical heteroatomic functional group migration.Chapter 4:The intermolecular dicarbofunctionalization of olefins with commercially available?-diketones or indoles and carboxylic acid has been developed under iron-catalyzed conditions via radical-polar crossover reaction.In this way,two adjacent C(sp³)-C(sp³)bonds can be constructed with a simple olefin by one step,which enriches the high efficient construction methods of C-C bonds.Chapter 5:Summary and prospect.