【作者】 张锋；

【导师】 宋秋玲；

【作者基本信息】 福州大学 ， 有机化学， 2021， 硕士

【摘要】 有机硼化合物是有机合成中重要的中间体,广泛应用于医药、功能材料、合成方法学等领域。有机硼化合物具有丰富的转化能力,能够快速构建碳碳键和碳杂键等。其中构建碳碳键是有机合成中合成新化合物最常用的方法,例如从传统的过渡金属催化的偶联反应、不饱和键的官能团化反应,到无过渡金属条件下的碳碳键的高效构建,再到后来利用光催化方法快速实现各种碳碳键的构建。近年来,有机硼化合物涉及的迁移反应取得了一些重要的进展,但是1,n-远程迁移(n≥3)以及自由基参与的迁移反应研究较少。本文针对目前有机硼化合物参与的迁移反应的局限及重要性,就三组分原位生成1,3-偶极子促进的1,4-迁移和光催化条件下对自由基诱导的有机硼化合物的迁移反应高效构建碳碳键展开了深入研究。本论文主要包含以下四部分内容:第一部分:综述了近年来有机硼化合物分别在无过渡金属参与、过渡金属参与以及自由基诱导下发生迁移反应的类型和特点。第二部分:无金属条件下,通过多组分反应高效合成α-羟基酮类化合物。α-羟基酮衍生物是有机合成中重要的合成前体,它们在合成方法学中具有丰富的转化和应用。该策略利用异腈,硼酸和醛分别作为三种反应底物时,反应非常高效,在温和条件下,以二氯甲烷或氯仿为溶剂,通过分子内的1,4-迁移反应即可方便构建α-羟基酮。该方法易于操作,具有良好的官能团耐受性和广泛的底物范围。此外,该策略能够对生物活性或药物分子进行后期修饰。第三部分:在可见光激发下,乙烯基氯化镁与烷基偕二硼化合物首先发生反应得到四配位硼中间体,全氟碘代烷烃作为自由基前体进攻乙烯基二硼酸盐络合物,通过自由基诱导的1,2-α-硼迁移可以得到二硼化的产物。该策略具有较高的原子经济性和广泛的底物范围,可以实现三组分的反应,并且方便高效地构建一系列高附加值的多氟烷基取代的1,2-二醇类化合物。第四部分:结论与展望。更多还原

【Abstract】 Organoboron compounds are important synthetic building blocks in organic chemistry,which have been widely used in pharmaceuticals,functional materials and synthetic methodology.Owing to the versatile transformations,organoboron compounds can be utilized for rapid constructions of carbon-carbon and carbonheteroatom bonds.Among them,the construction of carbon-carbon bonds is the most commonly utilized methods for the synthesis of new compounds in organic synthesis.It ranges from traditional transition metal-catalyzed coupling reactions and functionalization reactions of unsaturated bonds to the efficient construction of carbon-carbon bonds without transition metals as well as the late-on developed rapid construction of various carbon-carbon bonds via photoredox strategies.In recent years,great progress has been made in organoboron compound-involved migration reaction.However,the studies on 1,n-long distance migration reaction and radical enabled migration reaction are relatively rare.Given the limitations and importance of boron-involved migration reactions,an in-depth study was carried out in this thesis on1,4-migration reaction enabled by in situ-generated 1,3-dipoles via a three-component reaction and radical-induced 1,2-migration reaction promoted by photocatalysis for C-C bonds construction.This thesis mainly includes the following four parts:Part 1: We summarized the recent advances on migration reactions of organoboron compounds under transition-metal free,or enabled by transition metal or promoted by radicals.Part 2: The efficient synthesis of α-hydroxy ketones via a multi-component reaction under metal-free conditions.α-Hydroxy ketone derivatives are important synthetic precursors in organic synthesis.They have rich transformative applications in synthetic methodology.This strategy is highly efficient with isonitrile,boronic acid and aldehyde as the three reaction substrates.And α-hydroxy ketones were readily constructed via an intramolecular 1,4-migration reaction under mild conditions with dichloromethane or chloroform as solvent.This method features ease of execution,good functional group tolerance and a broad range of substrate scope.In addition,this strategy enables late-stage modifications of bioactive or drug molecules.Part 3: Under visible light irradiation,vinylmagnesium chloride reacts with alkyl diboron firstly to generate a tetracoordinate boron intermediate,then polyfluoroalkyl iodide is added as a radical precursor to attack the alkenyl diboronate complexes.Subsequently,a radical-induced 1,2-α-boryl migration leads to diborylated compounds.This method has a wide substrate scope and high atom economy,which could get access to a range of high-value polyfluoroalkylated 1,2-diol compounds via a three component reaction.Part 4: Conclusion and outlooks.更多还原