环丁烯酮类化合物合成及其应用研究
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摘要
作为一种在有机合成中非常有用的合成子,α-羰基二硫缩烯酮类化合物由于烷硫基强的推电子作用及羰基的拉电子作用赋予了该类化合物化学反应的多样性,即能与亲电试剂反应又可以和亲核试剂反应,因此广泛的应用于各种有机化合物以及重要天然产物的合成。
     在α-羰基二硫缩烯酮化学研究领域中,人们对α-乙酰基二硫缩烯酮类化合物的性质以及在有机合成中的应用进行了深入而广泛的研究。然而人们对α-丙酰基二硫缩烯酮类化合物的性质和应用的研究却非常少。我们研究小组多年来一直从事α-羰基二硫缩烯酮化学研究,利用不同的α-羰基二硫缩烯酮化学结构特征,通过多种合成策略对制备六元碳/杂环反应进行了深入研究。最近,我们又利用α-烯酰基二硫缩烯酮的结构特点,通过Nazarov反应合成了五元碳环化合物。本论文正是在上述实验结果以及深入分析α-丙酰基二硫缩烯酮类化合物的空间结构的基础上,以发展新基元合成反应和合成新方法为目标,利用在碱性条件下α-丙酰基二硫缩烯酮进行分子内成环反应,建立一种简单有效的合成环丁烯酮四元碳环的新方法。论文工作主要包括以下三个方面的内容:
     创建了一种以α-丙酰基二硫缩烯酮为底物,在碱性条件下合成环丁烯酮类化合物的简单有效的新方法。
     研究了在PTSA催化作用下环丁烯酮类化合物的开环反应,合成了一系列喹啉酮类化合物。
     用POCl3作催化剂,研究了环丁烯酮类化合物制备六元环内酯类化合物的反应。本文合成了十六种没有报道过的化合物,对这十六种化合物进行了1H NMR和13C NMR等表征确证。
α-Oxo ketenedithioacetals are emergimg as a kind of important intermediates in organic synthesis. Due to the push-pull interaction between the electron donating two alkylthio groups and the electron withdrawing group,α-Oxo ketenedithioacetals can react with various electrophilic reagents and nucleophilic reagent and have been widely applied in the synthesis of organic compounds as well as important natural product.
     In the fields ofα-oxo ketenedithioacetals chemistry, the properties and applications ofα-acetyl-ketene-S,S-acetals in organic synthesis have been deeply and extensively investigated. However, the research of synthetic applications ofα- ketene-S,S-acetals is very little. In recent years, our research group has devoted to the synthetic applications ofααoxo ketene-(S,S)-acetals. During the course of our studies on the chemistry of functionalized ketene-(S,S)-acetals, various six-membered carbon/heterocycles were produced on the basis of different annulation strategies.Recently,A series of highly substituted cyclopentadienes were obtained via a Vilsmeier reagent-mediated Nazarov cyclization–halovinylation reaction of divinyl ketones. On the basis of the above-mentioned experimental results as well as deeply analysizing the spatial structure ofα-propionyl ketene-S,S-acetals, under base conditions, a novel and efficient route to cyclobutenones has been developed via an intramolecular annulation reaction ofα-propionyl ketene-S,S-acetals.
     In this paper, my research mainly includes the following three aspects:
     1. A novel and efficient route to cyclobutenones has been developed via an intramolecular annulation reaction ofα-propionyl ketene-S,S-acetals under base conditions.
     2. A series of quinolin-4(1H)-ones were prepared by a thermal electrocyclic ring opening and successive electrocyclization reaction of cyclobutenones.
     3. In the presence of various acids, a series of polyfunctionalized 2H-pyran-2-ones were obtained via a ring-opening and ring-closing reaction of cyclobutenones in high yields. In this paper, 16 new compounds were synthesized and confirmed by 1HNMR and 13CNMR spectroscopies, etc.
引文
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