【作者】 刘卫兵；

【导师】 江焕峰；

【作者基本信息】 华南理工大学 ， 应用化学， 2010， 博士

【摘要】 氮、氧杂环化合物是一类非常重要的杂环分子,大多具有生物和药理活性。到目前为止,虽然有多种方法可以用来构筑氮、氧杂环化合物,但是寻找和开发新颖、高效、环境友好、反应条件温和以及操作简便的方法来构筑结构新颖的含氮、含氧杂环化合物骨架仍然有着持续的需求。本论文以炔酸酯为起始原料,围绕几类含氮和含氧的杂环分子的设计与合成方法而开展研究工作,具体包括以下几方面内容:1)以NaOH为催化剂,由炔酸酯和1,3-二羰基化合物为起始原料,经过氢烷基化反应和酯交换反应,成功地合成了多取代的α-吡喃酮衍生物和5,6-二氢-α-吡喃酮衍生物。该方法反应条件温和,操作简便,具有广泛的底物适应性,良好的收率。2)以NaOAc为催化剂,发展了一种“一锅法”五组分串联反应,由炔酸酯、丙二腈、醛和胺类化合物来合成多取代的1,2,3,4-四氢吡啶衍生物。该合成策略大大减少了合成步骤,避免了中间体的分离与纯化过程。3)在DABCO催化下,由炔酸酯和芳香醛经过[2+2+2]的环加成反应合成多取代的4-芳基-4氢-吡喃衍生物。该合成方法反应条件温和,操作简便,具有原子经济性,而且所使用的催化剂与原料廉价易得。值得注意的是,这个反应体系发生了醛基氧的迁移。到目前为止,有关醛基氧的迁移报道得很少。4)发展了一种新的共催化体系,并以DDQ为氧化剂,炔酸酯和1,3-二羰基化合物通过有效的加成氧化环化过程,成功地合成了多取代的呋喃衍生物。与文献已报道的合成呋喃的方法相比,此合成策略非常独特的优势在于,它是通过一个温和的氧化-关环的过程来构建呋喃骨架。这也是到目前为止采用氧化-关环的过程来合成呋喃骨架的首例报道。5)以AgBF4为催化剂,PIDA为氧化剂,发展了一种由炔酸酯和胺经过“一锅法”三组分串联反应合成多取代吡咯衍生物的新方法。该方法利用简单易得的原料,通过一个温和的氧化过程来合成吡咯衍生物。到目前为止,由炔酸酯和胺类化合物反应,通过一个氧化过程来合成吡咯衍生物的报道不多。这种合成策略还可以通过控制炔酸酯这类底物来构筑多取代的对称吡咯衍生物和非对称吡咯衍生物。更多还原

【Abstract】 Nitrogen- and oxygen-containing heterocyclic compounds are crucial moieties in a wide range of drug leads. Nitrogen- and oxygen-containing heterocyclic compounds of different ring sizes, with different substitution patterns and embedded in various molecular frameworks constitutes extremely important structure classes in the search for bioactivity. Despite the large availability of methods to construct nitrogen- and oxygen-containing heterocyclic compounds, there is still a strong need to further explore novel and being environmentally friendly synthetic methods to efficiently synthesize novel heterocyclic structures. We aim at the development of novel methodologies and catalysts for the synthesis of nitrogen- and oxygen-containing heterocyclic structural motifs from readily available alkynoates. The main work presented in this dissertation can be divided into six parts:1) We have successfully developed an synthesis of polysubstituted 5,6-dihydro-2H-pyran-2-ones and 2H-pyran-2-ones via the hydroalkylation of electron-deficient of alkynoates with activated methylenes and the transesterification using sodium hydroxide from alkynoates and 1.3-dicarbonyl compounds. This protocol provides several advantages such as mild condition, simple work-up procedure, high yield and compatibility to various substrates.2) A novel and convenient one-pot synthesis of multisubstituted 1,2,3,4-tetrahydropyridines via sodium acetate promoted five-component reactions under mild conditions from alkynoates, malononitrile, primary amine and formaldehyde. This multicomponent reactions (MCRs) offer several advantages such as atom economy and simpler procedures and equipment, time and energy savings, as well as environmental friendliness, and avoid the separation and purification of intermediates to maximize.3) DABCO induced [2+2+2] cycloaddition reaction to synthesize 4-Aryl-4H-pyrans, through reactions of of ethyl propiolate and aromatic aldehydes, is described. Operational simplicity, mild condition, atom economy, use of an economically convenient catalyst and starting materials are the key features of this protocol. Besides, to the best of our knowledge, reports about the synthesis of 4H-pyran derivatives through an oxygen migration process of aldehydes are rather rare, although there are many strategies for their synthesis.4) We have established a facile and efficient method to synthesize polysubstituted furans via tin(II) and copper(I)-involved addition/oxidative cyclization of alkynoates and 1,3-dicarbonyl compounds using DDQ as the oxidant. This methodology, comparing o traditional methods, not only provides a simple new way to construct polysubstituted furan derivatives, but also opens a brand new way to build oxygen-containing vinyl ether compounds through oxidation. To the best of our knowledge, it is the first reports about the synthesis of furans through an oxidative process.5) A facile and highly efficient C-N and C-C bonds formation method to construct pyrrole framework directly via one pot multicomponent reactions using AgBF4 as the catalyst and PIDA as the oxidant. In this protocol, various of amines and alkynes are all compatibility to this novel addition/oxidative cyclization reaction. Up to now, reports about the synthesis of pyrrole derivatives through an oxidative process are rather rare, although there are many strategies for their synthesis. Besides, this strategy provides an alternative way to construct symmetric and asymmetric polysubstituted pyrrole derivatives via controlling the starting materials of alkynoates.更多还原