Study On The Synthesis Of Enaminones And N-substituted Isoindol-1,3-dione Derivatives Usingα-diazo Arylketones As Reaction Partners

Diazo compounds are a class of privileged synthons in the organic synthesis,which are converted into highly active metal carbene or carbene intermediates by removing in situ nitrogen under the metal or metal-free catalytic conditions and subsequently react with appropriate nucleophiles to generate important functional organic molecules.These compounds could be applied to synthesiz nitrogen-containing products,but also take part in de-diazotizated domino reactions to realize the transformation of functional groups.In recent years,ɑ-diazo aryl ketones have become one of the focuses in organic chemistry.In this dissertation,ɑ-diazo aryl ketones as key substrates were reacted with different reagents to synthesize a variety of nitrogen/oxygen-containing small organic molecules through de-diazotizated transformation of functional groups.The starting materials have been maximized to convert into the desired molecules without isolation of intermediates,featuring atom economy,high synthetic efficiency and environmental friendliness.This details consists of the following four parts:In the first part,the research background of diazo compounds and the methods for constructing C-X bonds by de-diazotization are introduced.In recent years,a lot of reactions were investigation by using diazo compounds,including different metal-catalyzed cross-coupling reactions and radical transformations.In light of these report surveys,the topic basis,significance,novelty and research methods are put forward in this dissertation.In the second part,synergistic rhodium/copper catalysis enables new three-component coupling reactions of terminal alkynes and α-diazoketones and arylamines,allowing dediazotized carbene C-H insertion for the synthesis of functionalized(Z)-N-aryl enaminones with high stereoselectivity.The rection process involved the in situ generated Rh carbine,transmetalization,Insertion-migration and nucleophile addition sequence,results in the subsequent constuction of the C-N and C-C band.The excellent(Z)-selectivity was observed in the reaction,which is caused by intramolecular hydrogen bonds.In the third part,a novel radical-induced three-component reaction was developed.The three-component reaction of readily accessible N,N-dimethylanilines and N-hydroxyphthalimide with ɑ-diazo aryl ketones by using diacetoxyiodobenzene as an oxidant at room temperature has been established,enabling radical-triggered dediazotization for flexible synthesis of unprecedented ɑ-aminooxy-β-amino ketones.Serveral controlled experiments revealed that the reaction process involed in a radical mechanism.The reaction proceeded smoothly under metal-free condtions,leading to the construction of C-O and C-C bond with simultaneous realization of C(sp3)-H functionalization.In the fourth section,a new iodobenzene acetate-meidated three-componet reaction ofɑ-diazo aryl ketones with two molecules of N-hydroxy phthalimides was presented.The reactions worked well at room temperature,enabling radical-triggered dediazotization for the synthesis of structurally diverse diisoindole 1,3-diones.To further expand the scope of the reaction,N-hydroxysuccinimides were employed in this radical transformation to access dipyrrolidine 2,5-dione derivatives under the above-described conditions.Serveral controlled experiments indicated that the reaction process involed in a radical mechanism.The structures of the resultant products were characterized by NMR,IR and HRMS spectroscopy,some of which were further confirmed by X-ray diffraction analysis.