【作者】 李博；

【导师】 黄良斌；

【作者基本信息】 华南理工大学 ， 化学， 2024， 硕士

【摘要】 腈是一类基础的、重要的化合物,具有丰富的反应性,易被转化成各种其他高附加值化合物,另外,腈类化合物也具有广泛的生物活性,例如维拉佐酮用于治疗抑郁症,氟伏沙明作为治疗强迫症的药物。当同一分子存在多个氰基时具有特殊性质,有独特的应用价值,如己二腈每年的全球产能204万吨,是合成尼龙6,6的重要单体。相比较为成熟的腈类化合物的合成,1,n-二腈骨架的构建仍有待发展。设计适当的合成方法,在温和条件下高效地合成具有价值的二腈类化合物,同时兼顾绿色化学,实现较高的原子经济性,具有非常深远的理论价值和广阔的应用前景。本文通过探索了光催化自由基介导的1,1-二腈的1,4-氰基迁移反应,构建了一系列1,4-二腈以及其他腈类衍生物。具体内容包括以下部分:第二章的研究工作是以三氟甲基噻蒽盐作为三氟甲基自由基前体引发烯基丙二腈衍生物的氰基迁移,噻蒽自由基阳离子捕获氰基迁移后的碳自由基及β-消除,构建了一系列迈克尔受体类型的二腈产物。该方法无需光敏剂,三氟甲基噻蒽盐吸收蓝光发生均裂启动反应,首次实现了通过氰基迁移构建单一构型的1,n-烯基二腈产物。第三章的内容在第二章检测到噻蒽盐中间体的基础上,我们探究了该中间体的亲核取代反应。使用水作为亲核试剂,构建氰基醇类结构,该结构不稳定会进一步发生原位氢氰酸消除过程实现1,1-二腈第二个氰基的活化构建酮类衍生物。该反应条件温和,操作简单,底物兼容性较好。第四章的研究工作基于自由基介导的氰基迁移,我们将光介导单电子氧化羧酸脱羧过程与氰基迁移结合,通过单电子还原氰基邻位自由基质解构建烷基链1,4-二腈产物。在该反应中我们可以通过使用催化量的碱引发反应,质子化过程实现后续的羧酸向羧酸阴离子转化。该反应丰富了尼龙原料的种类,可以将各类三级烷基羧酸脱羧偶联至1,4-二腈结构中。更多还原

【Abstract】 Nitriles represent a fundamental and versatile class of compounds known for their rich reactivity.Moreover,nitrile-based compounds exhibit broad biological activities,with notable examples including vilazodone for depression treatment and fluvoxamine for obsessivecompulsive disorder.When multiple cyano groups are present in the same molecule,it exhibits special properties.For example,adiponitrile,with a global annual production capacity of 2.04 million tons,is an important monomer for synthesizing Nylon 6,6.Despite the well-established synthetic routes for mature nitrile compounds,the synthesis of 1,n-dinitrile frameworks need to be developed.The design of efficient synthetic methodologies for the synthesis of valuable dinitrile compounds under mild conditions,while upholding principles of green chemistry to achieve high atom economy,holds immense theoretical importance and offers vast application prospects.In this study,we explored the photocatalytic radical-mediated 1,1-dinitrile-to-1,4-cyanide migration reaction to construct a range of 1,4-dinitriles and other nitrile derivatives.Specific investigations include:Chapter 2 focuses on utilizing trifluoromethyl thianthrenium salts as trifluoromethyl radical precursors to induce cyano migration.Thianthrenium radical cations effectively capture the carbon radicals generated by cyano migration and β-elimination,facilitating the construction of a series of Michael acceptor-type dinitrile products.Notably,this method obviates the need for a photosensitizer,with trifluoromethyl thianthrenium salt initiating the reaction via blue light absorption,thereby achieving,for the first time,the construction of single-configurational 1,n-vinyl dinitrile products via cyanide migration.Building on the α-thianthrenium cyano species in Chapter 2,Chapter 3 delves into the exploration of nucleophilic substitution reactions involving thianthrenium salt intermediates.Leveraging water as a nucleophilic reagent,we synthesized cyanohydrin-like structures,which,upon subsequent in-situ hydrogen cyanide elimination,activate the second cyano of 1,1-dinitriles to yield ketone derivatives.This method offers mild reaction conditions,simplicity in operation,and favorable substrate compatibility.Chapter 4’s research,grounded in radical-mediated cyano migration,integrates photomediated single-electron oxidation decarboxylation of carboxylic acids with cyano migration.This strategy facilitates the deconstruction of 1,4-dinitrile products via single-electron-reduced cyano ortho radicals.By initiating the reaction with a catalytic amount of base,subsequent protonation enables the conversion of carboxylic acid to carboxylate anion.This method enables the coupling of various tertiary alkyl carboxylic acids to the 1,4-dinitrile structure,thereby broadening the scope of available nylon precursors.更多还原