| The oxygen heterocyclic skeleton structure is widely found in various natural products and medicines,for example,anthocyanins present in flower color substances;quercetin,which has antitussive,expectorant,and antiasthmatic effects;and has increased insulin sensitivity.Glitazone and so on.Therefore,the research on derivatives of oxygen-containing heterocyclic structure has always been the focus of attention of many chemists and pharmacists.Based on the tandem reaction of Michael addition,this article mainly carried out the following two parts to construct oxygen heterocyclic compounds:1.Using 11 kinds of p-QMs substituted with different substituents as starting materials and reacting with malononitrile,11 new4-arylbenzopyran-based oxygen heterocyclic derivatives were obtained.In the synthesis study using the Domino 1,6-conjugated addition aromatization tandem method,the method was optimized in this paper,using the o-hydroxyphenyl substituted p-methylene benzoquinone compound and malononitrile as the substrate,Firstly,5 kinds of alkalis and 6 kinds of solvents were screened,and then the reaction conditions such as temperature and concentration were investigated,and the dosage of alkali was optimized,which made the yield of the reaction as high as90%.2.Use a variety of activated olefins(such as cyclic olefins)to react with γ-halo-β-keto esters to construct various substituted 3(2H)-furanones,and optimize the synthesis method.The optimized The reaction conditions are: 100mol% Et3 N as a base,and CH2Cl2 as a solvent at room temperature can successfully obtain a variety of new succinimide substituted 3(2H)-furanone oxygen heterocycles in high yield(up to 96%)derivativeIn summary,the above two methods have the advantages of simple operation,green and safe,low cost,and strong universality.They are candidates for the discovery of benzopyran and 3(2H)-furanone oxygen heterocycles.The medicine has laid a theoretical foundation and has a certain practical value. |
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