【作者】 葛敏；

【导师】 鞠涛； 黄坤；

【作者基本信息】 扬州大学 ， 生物与医药硕士（专业学位）， 2024， 硕士

【摘要】 烯烃的双官能团化反应对构建复杂分子结构具有重大意义,在分子多样性的提高、合成效率的提升以及反应的可控性和选择性方面具有显著优势。同时,随着光催化的蓬勃发展,光催化烯烃的双官能团化反应得到了广泛发展,主要涉及三个过程:(1)烯烃的单电子氧化/还原,从而与亲核试剂/亲电试剂反应;(2)原位形成的自由基被烯烃捕获形成新的碳自由基,进而发生自由基-自由基偶联反应;(3)新生成的碳自由基也可发生单电子转移形成碳正离子或碳负离子中间体,再与亲核试剂或亲电试剂反应。值得注意的是,该类反应都需要氧化剂/还原剂和光敏剂。随着EDA络合物的发现和发展,可见光催化EDA络合物诱导的策略已广泛运用于C─C键、C─N键、C─S键、C─B键的构建。该类方法具有不需使用光敏剂,反应条件简单,对环境友好等优点。但目前该策略在烯烃的双官能团化反应的研究还存在一定的挑战。本文围绕光诱导EDA络合物促进烯烃的双官能团化实现重要杂环化合物的构建展开研究。主要包括三个方面的研究内容:1.光诱导EDA络合物促进烷基卤化物、N-烷基吲哚参与的烯烃双官能团化及环化反应多取代四氢呋喃作为重要的骨架,广泛存在于各种天然产物和药物分子中。本章开发了一种新型的烷基卤化物、吲哚和乙酸锌三组分形成的EDA络合物。基于该EDA络合物,我们实现了可见光诱导的烯烃双官能团化反应,构建了一系列吲哚衍生物。在此基础上,进一步通过羰基捕获反应中生成的碳正离子,合成结构多样的多取代四氢呋喃类化合物。该反应具有原料简单易得,底物范围广,不需要光催化剂、不需要氧化剂和还原剂等优点。2.光诱导EDA络合物促进烷基卤化物、水参与的烯烃双官能团化及环化反应进一步利用该EDA络合物,实现光诱导N-甲基吲哚催化的烷基卤化物、水参与的烯烃碳羟基化/环化反应,构建了一系列三级醇类化合物和半缩酮类化合物。该方法首次使用N-甲基吲哚为催化剂,并且具有反应条件温和、化学选择性高,底物范围广等特点。3.光诱导EDA络合物促进烷基卤化物、芳胺参与的烯烃双官能团化及环化反应基于现有的EDA络合物,我们进一步选用芳胺作为亲核试剂来代替水,实现光催化烷基卤化物、芳胺参与的烯烃碳胺化反应,高效地合成了一系列含四氢呋喃环的仲胺类化合物。更多还原

【Abstract】 The difunctionalization of alkenes is of great significance for constructing complex molecular structures,and has advantages in improving molecular diversity,synthesis efficiency,and reaction controllability and selectivity.Over the past few decades,visible-light photoredox catalysis has been applied widely in the difunctionalization of alkenes,and mainly involves three processes:(1)Oxidation/reduction of the alkenes to react with a nucleophile/electrophile;(2)the direct addition of in-situ free radicals to alkenes,which can generate new carbon radicals and then undergo a radical-radical coupling or a radical-polar crossover;(3)a single electron transfer(SET)event leads to a carbocation or carbanion,which can react with a nucleophile or electrophile respectively,while these reactions necessitate the use of oxidants/reductants and external photosensitizers.Subsequently,the photoactivity of electron donor-acceptor(EDA)complexes was discovered and used to construct various chemical bonds,such as C─C bonds,C─N bonds,C─S bonds,C─B bonds.This strategy is environmentally friendly,high selectivity and simple reaction conditions.However,there are still certain challenges in the research of difunctionalization reactions of alkenes.The dissertation focuses on the construction of important heterocyclic compounds through the difunctionalization and cyclization of alkenes by light-irradiation of EDA complexes.The research mainly includes three aspects:1.Photo-induced difunctionalization and cyclization of alkenes,alkyl halides and Nalkylindoles via an EDA-complexPolysubstituted tetrahydrofurans,as important skeletons,are widely present in various natural products and drug molecules.This chapter developed a novel EDA complex formed by alkyl halides,indole,and zinc acetate.Based on this EDA complex,we realized the visible light induced difunctionalization of alkenes and constructed a series of indole derivatives.On this basis,we utilized the intramolecular C=O double bonds to capture newly generated carbon cation intermediates and promoted the intermolecular cyclization to obtain polysubstituted tetrahydrofurans.This reaction has the advantages of simple and easily obtainable raw materials,wide substrate range,no need for photocatalysts,no need for oxidants and reducing agents,etc.2.Photo-induced difunctionalization and cyclization of alkenes,alkyl halides and water via an EDA-complexFurther utilizing this EDA complex,we developed the photo-induced N-alkylindole catalyzed olefin carbohydroxylation/cyclization reactions with alkyl halide and water to construct a series of tertiary alcohol compounds and semiketal compounds.Importantly,these transition-metal-free reactions first realize N-alkylindole as the catalyst and has the characteristics of mild reaction conditions,high regio-and chemo-selectivities,and good functional group tolerance,easy scalability and potential for product derivatization.3.Photo-induced difunctionalization and cyclization of alkenes,alkyl halides and aromatic amines via an EDA-complexBased on existing EDA complexes,we further selected aromatic amines as nucleophilic reagents to replace water,achieving the photo-induced carboamination reactions of olefin with alkylhalide and aromatic amine,and efficiently synthesizing a series of secondary amine compounds containing tetrahydrofuran rings.更多还原