PDMS海绵负载可见光催化剂及其在交叉脱氢偶联反应中的应用

发布时间：2018-04-01 18:17

本文选题：可见光催化　切入点：交叉脱氢偶联反应　出处：《深圳大学》2017年硕士论文

【摘要】：光催化反应是一种绿色清洁的反应途径,通常以可见光作为能源来诱发化学反应的进行。可见光诱导光氧化还原反应策略已经被广泛应用于活性有机小分子的合成中。通过光化学反应,化学家们已经实现了醛酮羰基α位的取代反应,环加成反应,α氨基碳自由基反应,芳烃及烯烃的三氟甲基化,亚胺阳离子为中间体的反应等,成功地构建了C-C键、C-O键、C-P键、C-N键。本论文介绍了可见光催化在交叉脱氢偶联反应中的研究进展,并围绕可见光催化剂的负载做了相关工作:首先,选择具有较好透光性和稳定性的聚二甲基硅氧烷(PDMS)作为有机海绵载体;然后利用表面修饰技术(空气等离子体)在海绵表面引入亲水性的羟基官能团,并用2-甲基丙烯酰基乙基三甲基氯化铵(METAC)进行自由基聚合修饰;最后,用离子交换的方法在PDMS-MATAC海绵上负载玫瑰红(Rose Bengal,RB)染料,从而获得海绵负载的可见光催化剂。所获得的海绵光催化剂通过SEM、EDS等表征手段进行定性分析,并通过1H NMR进行定量表征,负载量为0.01mmol/g。催化活性方面,PDMS-RB海绵光催化剂对于四氢异喹啉类衍生物与硝基甲烷、丙酮、重氮乙酸乙酯类反应具有普遍的适用性,取得了预想的催化效果。传统的二氧化硅、高分子聚合物、金属有机框架和石墨烯等固体催化剂载体需要通过过滤、离心方法来实现催化剂的分离,而PDMS海绵载体光催化剂仅需通过简易操作,反应结束后直接将海绵夹出反应体系就能实现催化剂与反应物的分离。另外,对该催化剂的回收利用进行研究,以四氢异喹啉与硝基甲烷为模型反应,催化剂循环利用次数≥15次(收率≥85%),且催化活性没有明显降低。为进一步验证PDMS-RB海绵光催化剂在工业应用中的可行性,组建一个连续流动的反应装置(包含一个蠕动泵、一段玻璃管和一条灯带)。在测试以N苯基四氢异喹啉与硝基甲烷为模型的放大量反应,仅需48 h就取得了88%的柱层析收率,此时催化剂的用量仅为1.4 mol%。这是一个很容易构建的简易装置,任何一个简易的有机化学实验室均可搭建这种装置来做大规模的合成反应。此外,将玫瑰红光催化剂的催化反应类型做了进一步的拓展,实现了N芳基四氢异喹啉类酯与马来酸酐类衍生物的[3+2]环加成反应。首次将玫瑰红结合过渡金属盐实现了叔胺类α位C-H键烯基化反应。PDMS海绵经过共价键修饰,以谷氨酸为Linker,成功将玫瑰红、脯氨酸连接在PDMS海绵上,制备了疏水性的双功能催化剂。以芳基四氢异喹啉与丙酮的曼尼烯反应为模型,验证了该催化剂以水作为溶剂的催化效果。总之,通过表面改性技术对PDMS海绵高分子材料进行修饰,修饰后的海绵通过离子交换技术与可见光催化剂玫瑰红结合,成功地开发了一种简单、高效的有机海绵光催化剂。在可见光诱导下,对于CDC反应,海绵光催化剂显示出优良的催化活性。PDMS有机海绵光催化剂具有:稳定性强、易于回收、重复利用次数多、反应活性高、易放大量实验等优点。结果表明PDMS海绵是一种很有前途的非均相催化载体。在PDMS海绵上固定其他催化剂的研究(包括多功能催化剂和实现立体选择性的交叉脱氢偶联反应)相关的更有趣的转换实验正在进行中。
[Abstract]:The photocatalytic reaction is a way of green cleaning, usually in the visible light as the energy to induce chemical reactions. The synthesis of visible light induced photo oxidation reduction reaction strategy has been widely used in active organic molecules. Through photochemical reactions, chemists has achieved the substitution reaction of aldehyde and ketone carbonyl alpha bits, cycloaddition, alpha amino carbon free radical reaction, aromatics and olefins three fluoromethylation, iminium cation intermediate reaction, the successful construction of the C-C key, C-O key, C-P key, C-N key. This paper introduces the research progress in visible light catalytic dehydrogenation cross coupling reaction. And around the load of visible light catalyst to do related work: first, with good transparency and stability of two polydimethylsiloxane (PDMS) as organic sponge carrier; then using surface modification technology (air plasma) in the sea The introduction of hydrophilic hydroxyl groups on the surface of cotton, and 2- methacryloyl ethyl three methyl ammonium chloride (METAC) modified by free radical polymerization; finally, using the method of ion exchange in PDMS-MATAC sponge load Rose (Rose Bengal, RB) to obtain dye, visible light catalyst load. The obtained sponge sponge light catalyst by SEM, EDS were characterized by means of qualitative analysis and quantitative characterization of 1H by NMR, the load of 0.01mmol/g. catalytic activity, PDMS-RB sponge photocatalyst for four isoquinoline derivatives and nitro - methane, acetone, ethyl diazoacetate reaction has general applicability, achieved the expected catalytic effect the traditional silica, polymers, metal organic frameworks and graphene solid catalyst carrier by filtration, centrifugation to separate the catalyst, and PDMS sponge The carrier photocatalyst only by simple operation, after the reaction will be directly isolated from sponge clamp reaction system can realize the catalyst and the reactants. In addition, research on the recovery of the catalyst utilization, with four isoquinoline and nitromethane as a model reaction, the catalyst recycling more than 15 times (yield = 85%) and, without loss of catalytic activity. In order to further verify the feasibility of PDMS-RB sponge photocatalyst in industrial application, the formation of a continuous flow reactor (including a peristaltic pump, a glass tube and a lamp). In the test with N four phenyl isoquinoline and nitromethane as a reaction the model, only 48 h made column yield of 88%, the amount of catalyst is 1.4 mol%. which is a simple device, it is easy to construct, any simple organic chemical laboratory can build this Device to do large-scale synthesis. In addition, the red rose type catalytic reaction catalyst was further expanded, [3+2] ring N four aryl hydrogen isoquinoline derivatives and ester of Maleic Anhydride Addition Reaction for the first time. The red roses with transition metal salts to achieve tertiary amine ene C-H key alpha the reaction of.PDMS sponge through covalent modification, such as glutamic acid Linker, successfully rose red, proline connection in PDMS sponge, hydrophobic bifunctional catalysts were prepared. The Manny ene reaction of aryl four isoquinoline with acetone as a model, proved the catalyst with water as solvent catalytic effect in short, through the surface modification technology of modified PDMS foam polymer material, the modified sponge rose by ion exchange technique is combined with visible light catalyst, successfully developed a simple and efficient machine with the sea Cotton. Photocatalyst under visible light induced, for the CDC reaction, sponge photocatalyst showed excellent catalytic activity of.PDMS organic light sponge catalyst: strong stability, easy to recycle, reuse times and high reactivity, easy to put a large number of experiments. The results show the advantages of the PDMS sponge is a very promising heterogeneous catalytic carrier. Research on fixed other catalysts in PDMS sponge (including multifunctional catalyst and cross dehydrogenative coupling for stereoselective conversion) more interesting experiments are underway.

【学位授予单位】：深圳大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O643.36

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