紫外光诱导烯烃三氟甲基化反应的研究

发布时间：2018-04-08 16:12

本文选题：三氟甲基化　切入点：双官能团化　出处：《哈尔滨工业大学》2016年硕士论文

【摘要】：三氟甲基特殊的物理性质和化学性质,使得其广泛应用于医药、农化学品和材料等领域。因此,向有机分子引入三氟甲基已成为当今有机合成的热点研究领域。几十年来,化学家实现了各种不同类型的引入方法,但有些方法存在反应条件苛刻,原料难得及选择性差等缺点。近年来,随着有机光化学研究的发展,三氟甲基化反应的研究取得了重大突破。烯烃的双官能团化反应,即通过双键向有机分子引入两种官能团的反应,在有机合成中具有无限的潜能。实现烯烃的双官能团化重要反应策略之一是通过烯烃的三氟甲基化,在构建C-CF3键时,引入C-X,C-C,C-H,C-O,C-N或C-S键。本文主要研究利用光化学反应,向烯烃引入三氟甲基实现烯烃的双官能团化,并构建分子内的C-C键。α,β-不饱和芳香酮作反应原料,通过对三氟甲基试剂、溶剂、光敏剂和光源等反应条件进行筛选优化,确定最优反应条件:在N2保护下,三氟甲基亚磺酸钠(CF3SO2Na)提供三氟甲基源,二苯甲酮(BP)作光敏剂,干燥乙腈为溶剂,在500 W中压汞灯紫外光照射下合成一系列三氟甲基化菲酚类衍生物。在最优条件下,拓展了25种含有不同官能团的α,β-不饱和芳香酮,均取得良好收率,进而研究不同官能团对该反应的影响。通过加入自由基捕获剂TEMPO的控制实验,气相-质谱仪检测到TEMPOCF3,推测该方法可能的反应机理:三氟甲基试剂在光敏剂和紫外光诱导下产生三氟甲基自由基(CF3.),和光照底物α,β-不饱和芳香酮的双键发生自由基加成,形成以碳为中心的自由基,然后进攻另一苯环邻位进行分子内环合,形成苯基自由基,最后,伴随羰基的烯醇化和氢质子的离去,生成目标产物。
[Abstract]:Because of its special physical and chemical properties, trifluoromethyl is widely used in medicine, agricultural chemicals and materials.Therefore, the introduction of trifluoromethyl to organic molecules has become a hot research field of organic synthesis.In recent decades, chemists have realized a variety of different methods of introduction, but some methods have some shortcomings such as harsh reaction conditions, rare raw materials and poor selectivity.In recent years, with the development of organic photochemistry, the study of trifluoromethylation has made a great breakthrough.The bifunctional reaction of olefins, that is, the introduction of two functional groups to organic molecules by double bonds, has unlimited potential in organic synthesis.One of the important strategies for the bifunctional reaction of olefin is the trifluoromethylation of olefin. When the C-CF3 bond is constructed, C-XG C-C, C-H, C-O, C-N or C-S bonds are introduced.In this paper, using photochemical reaction to introduce trifluoromethyl to olefin to realize difunctional group of olefin and to construct intramolecular C-C bond. 伪, 尾 -unsaturated aromatic ketone is used as raw material.The reaction conditions such as Guang Min and light source were screened and optimized to determine the optimum reaction conditions: under the protection of N2, sodium trifluoromethylene sulfonate (CF3SO2Na) provided trifluoromethyl source, benzophenone BP) as Guang Min agent, and dry acetonitrile as solvent.A series of trifluoromethylphenolic derivatives were synthesized by UV irradiation of 500 W medium pressure mercury lamp.Under the optimum conditions, 25 kinds of 伪, 尾 -unsaturated aromatic ketones with different functional groups were developed and the yield was good. The effect of different functional groups on the reaction was studied.By adding free radical trapping agent TEMPO to control experiment,TEMPOCF3 was detected by gas phase mass spectrometer, and the possible reaction mechanism of this method was speculated: trifluoromethyl radical was induced by Guang Min and ultraviolet light, and free radical addition was produced by double bond of 伪, 尾 -unsaturated aromatic ketones.Carbon-centered free radicals were formed, and then attacked another benzene ring for intramolecular cyclization to form phenyl radical. Finally, with the enolation of carbonyl group and the departure of hydrogen proton, the target product was formed.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：O621.25

【相似文献】