Intermolecular N-arylation Reaction Research Based On The N-heterocyclic Iodide Ylide

The area of trivalent iodine chemistry has caught attention in the field of mordem synthetic organic chemistry.Trivalent iodine reagents are valuable for their wide application in modern organic synthesis,generally these reagents require only mild reaction conditions and can perform good chemical reaction properties during the reaction.The Iodine ylide,as an important research field of trivalent iodine chemistry,can be prepared by oxidation of a suitable substrate using a trivalent iodine reagent.Due to its unique structure,it can be used as intermediates in the reaction process or as substrates to transform into more valuable structural skeletons.Nitrogen-containing heterocyclic rings,especially N-aryl heterocyclic compounds,have specific properties in pharmacy,biology,and chemistry,and thus received extensive attention.The N-arylation reaction is one of the effective ways to build the C-N bond.In recent decades,Buchwald and Hartwig have made a great contribution to the metal-catalyzed N-arylation reaction,forming a mature pathway for the build of C-N bond.In addition,N-arylation reactions under metal-free conditions are also being developed,providing a novel green synthesis routes for the construct of C-N bond.In this paper,the iodine ylide structure is oxidized by a trivalent iodine reagent to generate an N-arylated heterocyclic compounds by intermolecular rearrangement and the main research content is as follows:The first part is,from the simple and readily available quinoline compounds,the corresponding ylide are obtained by trivalent iodine reagents in situ oxidation.Then under the catalysis condition of cheap metal copper powder,the C-I bond is broken to obtain 3-iodo-N-arylated quinolinone skeleton.Crossover experiments show that the reaction involves an intermolecular rearrangement process.And part two,pyrazole compounds are used as substrates to obtain NH-pyrazolium iodonium salts in situ under oxidation of trivalent iodine reagents then,an intermolecular arylation reaction occurs under the mediate of 1,10-phenanthroline and base.Mechanism study found that,when the iodine ylide is isolated and reacted as a substrate,the pyrazole-bifunctionalized product can be directly obtained without the participation of transition metal and base.Further mechanistic studies show that this reaction also undergoes intermolecular aryl migration.Without making any separation and purification of the reaction intermediates in whole reaction process,we can quick and easy to synthesis N-arylated compounds.Through this "one-pot;two-steps" operation method,both C-N bond and C-1 bond can be bulit simultaneously.This type of reactions have the characteristics of better atomic economy,green cheapness,and strong practicality.The product structure is usually an important skeleton in drug active molecules such as antibacterial,antioxidative and anticancer properties.Therefore,the method of N-arylation of C-N bonds developed in this dissertation is of great value and significance.