【作者】 邵玉田；

【导师】 夏吾炯；

【作者基本信息】 哈尔滨工业大学 ， 化学工程与技术， 2012， 博士

【摘要】 有机光化学反应是指有机分子在光诱导条件下发生的反应，具有操作简单、反应快、副产物少等优点，符合绿色化学的要求，因而受到广大有机光化学爱好者的广泛关注。作为众多有机光化学反应类型的其中之一，有机光化学重排反应不但具有环保、高效的优点，而且在合成复杂结构的化合物及探索新型化合物方面具有至关重要的作用。本论文以探索新型有机光化学重排反应为目标，以肉桂酸酯及芳香类γ,δ-环氧酮类化合物作为研究对象，在液相中研究了它们的光化学反应过程，所发现的新型有机光化学重排反应提出了可能的反应机理，并对其在有机合成领域的潜在应用价值进行了初步分析。在液相环境中研究了具有不同结构的肉桂酸酯衍生物的光化学反应行为，发现了这类化合物在液相环境中经过一个新型有机光化学重排反应过程产生异色酮衍生物。以原料转化率及光化学产物的收率为衡量标准，采用气相色谱作为分析手段讨论了反应介质、光照时间对该新型光化学重排反应的影响，结果表明以500W高压汞灯作为紫外光来源，室温条件下，以充分排除空气的干燥苯溶液作为反应介质时，该光化学重排反应产物的收率最高达89.6%；底物结构对光化学反应行为影响的分析结果显示底物结构中甲酰基氢与酯羰基α-位氢的共同存在是该重排反应过程能否顺利发生的关键因素；分析了该新型光化学重排反应的机理及在合成异色酮类化合物方面潜在的应用性；初步讨论了光化学不对称合成异色酮衍生物的可能性。研究了芳香类γ,δ-环氧酮化合物在液相环境中的光化学反应行为，发现了这类光化学底物经过Norrish type-Ⅱ与无路易斯酸催化的semi-pinacolrearrangement之间的新型光化学串联反应产生为苯并环丁酮类化合物。条件优化结果表明以经过除氧的干燥苯溶液作为反应介质，以450W中压汞灯提供的经过石英玻璃过滤后的紫外光作为激发光源时，苯并环丁酮的分离产率最高可达76.7%；分析了底物结构对该光化学重排反应的影响发现底物结构中酮羰基γ-与δ-位氢的共同存在是该光化学重排反应能否发生的关键；提出了可能的光化学反应机理并初步讨论了该新型光化学重排反应在其他结构的γ,δ-环氧酮体系中的普适性及合成苯并环丁酮衍生物方面的应用性。采用450W中压汞灯作为激发光来源，在充分排除空气的干燥苯溶液中研究了带有非末端环氧基的芳香类γ,δ-环氧酮的光化学反应行为，发现了该类分子可以经过光诱导环氧重排与分子内1,5-自由基环化之间的新型光化学串联反应转化为苯并环戊酮衍生物。条件优化实验结果表明以450W中压汞灯提供的经过石英玻璃过滤后的紫外光作为激发光源，同时采用没有任何添加剂的干燥苯溶液作为反应介质时，苯并环戊酮分离收率可达62.0%以上；提出了可能的光化学反应机理；初步分析了该新型光化学重排反应在苯并环戊酮衍生物合成方面的应用性；确定了苯并环戊酮的立体构型。更多还原

【Abstract】 Organic photochemical reaction (OPR) focuses on the conversion frommolecule(s) to other molecule(s) induced by light, which shows many advantages,such as simple operation and post-processing, almost no waste is generated, littleside-products, et al. Photochemical rearrangement reaction is an important OPR dueto its application for the preparation of highly functionalized compounds whichwould be difficult to access with standard chemical reactions in the ground state andtotal synthesis of natural products. In the thesis, cinnamate esters and aromaticγ,δ-epoxy ketones were selected as the research objects, the photochemistry of themwas studied in solution under variable conditions.The photochemistry of cinnamate esters was studied using500Whigh-pressure mercury lamp as light resource in different solution at roomtemperature. It’s found that cinnamate esters could be conversed to polysubstitutedisochromanone derivatives via a novel photochemical rearrangement reaction. Theinfluence of solvents, time of irradiation on this reaction was studied by GC basedon the conversation of substrate and yield of photoproduct, the results showed thatthe highest yield of isochromanone was89.6%when the experiment was advancedin degassed anhydrous benzene with500W high-pressure mercury lamp as lightresource. After studies on the proposed mechanism of this novel photochemicalrearrangement reaction, the application of it to aromatic α,β-unsaturated ketone andpreparation of isochromanone derivatives were discussed preliminarily. At last, thephotoinduced asymmetric synthesis of isochromanone was studied in solution.The preparation of aromatic γ,δ-epoxy ketones and photochemistry of themwas studied in solution and a novel photorearrangement reaction was found, namedNorrish type-Ⅱ/semi-pinacol rearrangement tandem reaction. After theoptimization of conditions, it can be concluded that the yield photoproductbenzocyclobutanone was highest with anhydrous degassed benzene solution assolvent and450W medium-pressure mercury lamp as light source. Additionally, thephotorearrangement reaction couldn’t be happened if the γ-H or δ-H of ketonecarbonyl was substituted with methyl. At last, the proposed mechanism andapplication of it in organic synthesis were discussed simply.The photochemistry of aromatic γ,δ-epoxy ketones with substituted epoxygroup was studied in solution using450W medium-presure mercury lamp as lightsource. The results revealed that these substrates could be conversed tobenzocyclopentenones by a novel photoinduced epoxy rearrangement/1,5-biradicalscyclization tandem reaction. The result of analysis of solvent, wavelengths and lewis acid on this photorearrangement reaction showed anhydrous degassedbenzene was the best solvent, the yield of benzocyclopentenone could be higherthan80.0%under the optimized condition. The proposed methanism of thisreaction and the potential application of this new photochemical rearrangementreaction to synthesis of benzocyclopentenone were studied be analysis theabsolutely structure of the photoproduct.更多还原