【作者】 欧阳艳；

【导师】 董德文；

【作者基本信息】 东北师范大学 ， 有机化学， 2010， 博士

【摘要】 随着世界范围内对环境问题的日益重视,传统的有机反应面临挑战,有机溶剂的使用受到限制。如何从源头上消除或减少废物排放对有机合成而言是极具挑战性的研究课题。近年来,水作为有机合成反应介质的报道相继出现。因为它是一种廉价、安全、无污染的绿色溶剂,完全克服了大多数有机溶剂带来的易燃、易爆、易挥发、容易污染环境的缺点,水相中的有机合成越来越成为有机化学研究的热点。目前,水介质中的有机反应已经被成功应用到氧化、还原、缩合、迈克尔(Michael)加成、维悌希、偶联、取代、有机光化学、自由基反应等诸多反应中。?-羰基二硫缩烯酮类化合物是有机合成中的重要中间体,它的结构特征赋予了其化学反应的多样性,从而被广泛应用于有机合成中。近十年来,我们课题组一直致力于?-羰基二硫缩烯酮的合成与应用研究,取得了一系列研究成果。特别是成功实现了以水为介质和无溶剂条件下,?-羰基二硫缩烯酮作为硫醇替代试剂的硫缩醛/酮化和硫杂迈克尔加成反应,解决了低分子量硫醇在反应中的环境与安全问题。为了在更多的反应中减少有机溶剂的使用,开发?-羰基二硫缩烯酮新型的水相有机反应仍是我们课题组研究工作的重要内容。本论文致力于发展?-羰基二硫缩烯酮在水介质中的新型有机反应。以?-羰基二硫缩烯酮的合成为基础,以发展新基元合成反应和合成新方法为目标,创建了一种新的[4 + 2]成环策略,由此建立了一种通用性强、步骤简洁的合成多取代吡喃酮化合物的新方法。同时,从?-羰基二硫缩烯酮类化合物出发,经羟醛缩合反应分别得到单、双缩合产物?-烯酰基二硫缩烯酮;经氨基噻吩一步合成具有生物活性的噻吩并喹啉杂环化合物,为噻吩并喹啉类化合物的合成提供了一种操作简单、条件温和、步骤简洁的新方法。论文工作主要包括以下三方面的内容:1.在水介质中、碱催化下,以2-(1,3-亚乙/丙二硫)亚甲基-2,4-戊二酮和芳醛为底物,通过羟醛缩合反应设计合成了一系列新的单缩合、双缩合及不对称缩合产物?-烯酰基二硫缩烯酮。该方法操作简单、条件温和,产物易于分离,产率高,化学选择性好。2.创建了[4 + 2]成环策略。利用[4 + 2]成环策略在水介质中、碱催化下,?-乙酰基二硫缩烯酮和不同的芳醛反应,先后通过羟醛缩合、共轭加成-消除的两步串联反应简洁地合成了一系列具有生物活性的二氢吡喃酮。3.从?-二羰基化合物出发设计合成了系列新的氨基噻吩化合物,后者在BF3·Et2O催化下进一步环合得到了一系列噻吩并喹啉,该反应操作简单、条件温和,产物易于分离,产率高,为噻吩并喹啉类化合物的合成提供了一种步骤简洁的新方法。更多还原

【Abstract】 Environmental issues have attracted considerable attention of the world. Traditional organic reaction is facing the challenge for the limitation of the use of organic solvent. It is challenging research topic to avoid or reduce the waste for organic synthesis. Reacently, it was widely reported that water was used as organic reaction medium. Bing an easily available, cheap, safe and benign solvent, water avoid the disadvantages of most organic solvent, such as flamable, explosive, volatile and pollution.Organic synthesis in aqueous media has become active area of organic chemistry. Today, water as solvent has been applied to many organlic reactions such as oxidation, reduction, condensation, cycloaddition, coupling, Wittig, organic photochemistry, radical reactions.α-Oxo ketene-(S,S)-acetals are a kind of versatile intermediates used in organic synthesis. Base on its structure, it is widely used in organic synthesis. In the past decade, we have been devoting our efforts towards the synthesis and applications onα-oxo ketene-(S,S)-acetals and achieved interesting results. In particular, we successfully appliedα-oxo ketene-(S,S)-acetals as thiols equivalents in thioacetalization and Michael addition reactions in aqueous or solvent-free conditions, sorting out the environment and safety problems of thiols with low molecular weight used in organic reactions. To avoid the use of organic solvent, we has been investigating the novel organic reaction in water.In the present thesis, we devort our effort to develop novel organic reaction withα-oxo ketene-(S,S)-acetals in water. Aming to develop new basic reactions and new synthetic methods we developed a new [4 + 2] synthetic strategy from ?-oxo ketene-(S,S)-acetal chemistry based on synthetic design, providing a general and simple route to polysubstituted pyranons. Mono- and double condensed ?-alkenoyl ketene-(S,S)-acetals aere synthesized through aldol condensation reactions of ?,?-diacetyl ketene-(S,S)-acetals. An efficient synthesis of thieno[2,3-b]quinolines is developed from 2-aminothiophens. The thesis mainly include three aspects:1. The synthesis of mono-condensed and double condensed???-alkenoyl ketene-(S,S)-acetals has been developed via the aldol condensation of ?,?-diacetyl ketene-(S,S)-acetals with aromatic aldehydes in the presence of NaOH in water. The simple procedure, mild conditions, easy separation, high yields, high chemoselectivity, and especially that in relation to the current environmental concerns, make this protocol most attractive for academic research and practical applications.2. [4 + 2] Annulation strategy is developed. Dihydropyranones were synthesized via the formal [4+2] annulation of readily available ?-acetyl ketene-S,S-acetals with various aldehydes, involving tandem aldol reaction and conjugate addition-elimination reaction, in the presence of NaOH in water.3. A series of 2-aminothiophens were designed and synthesied, which were converted into substituted thieno[2,3-b]quinolines catlyzed BF3·Et2O. The thieno[2,3-b]quinoline synthesis is associated with advantages such as simple procedure, mild condition and high yields.更多还原