新型芳基甲基自由基晶体的合成、结构及功能研究

发布时间：2018-04-25 09:35

本文选题：二芳甲基自由基 + 三芳基甲基碳正离子自由基　；参考：《中国科学技术大学》2017年硕士论文

【摘要】：本论文主要论述了芳基甲基自由基功能材料的研究进展以及质子化效应在有机分子中的应用。在本实验室之前的研究工作中,我们合成出一种稳定的发光性的中性自由基底物obip和obip-CHO,在此基础上,进一步拓展功能自由基材料的研究。首先,通过简单的一锅法设计合成了两种稳定新型的二芳甲基单自由基5和二芳甲基三自由基7,两种自由基由于各自不同的电子结构和堆积状态,展现出不同的性能。并且5在HC1O4溶液中酸化后,可以容易地转变为7。跟5相比,7具有更高的量子产率并且近红外吸收增强,这是由于7中存在独特的质子分享型氢键。另外,在酸碱气体的刺激下,5和7之间的磷光、颜色和磁性性质可以互相转换,同时相应地给出不同EPR信号。因此,质子分享型氢键可以作为5跟7的开关:当被质子化时,开关"开"7稳定存在,EPR呈现七重信号峰,具有荧光性能;当去质子化,开关"关"7转变成5,EPR呈现单信号峰,发光较弱。7对酸碱性气体产生的这种刺激响应性能,使其可以被制备成为氨气的磷光传感器件。这项工作为研究新的通过外部刺激可以可逆的转变颜色、发光、磁性的多功能材料提供一种新型合成方法,以及为制备新型传感器件提供了灵感。其次,在上一章的研究基础上,我们又继续培养了一种盐酸体系下的单晶,该晶体中具有通过多重氢键相互作用形成的有趣的三环式[6.2.0.0]构型。此外,我们也根据单晶的晶体学证据,首次报道了一种室温下未解离的HC1水合物单晶及其水分子二聚体具有的非常规顺式-线性构象。也证明了该独特现象是由三环式构型的环几何效应引起的。本章工作的重要性在于探索出室温下也可以得到未解离的HC1水合物单晶,和没有穴腔束缚作用也可以得到顺式-线性构象的水分子二聚体。我们的工作为室温下探索HC1-H20体系新型构型提供帮助。最后,基于实验室之前报道的三种新型的三芳基甲基碳正离子自由基,发现这三种三芳基甲基碳正离子自由基盐是同分异构体,并且在300 K时表现出不同的磁化率值。本章通过简单的"一锅法"合成一种三芳基甲基碳正离子自由基(标为TAM+··Cl-),有趣的是,当将其质子化后,"cis"TAM+··Cl-转化成"trans"三芳基甲基碳正离子自由基(标为HTAM2+··2ClO4-·H2O)。如此明显的构象改变,是由一个环外羰基氧原子和被质子化的吡啶氮原子形成的分子内氢键引起的。同时,构象的改变也带来晶体结构和性能的改变,与反式构象HTAM2+··2ClO4-·H20相比,顺式构象TAM+··Cl-拥有一维高疏水通道。另外由于构象的改变,二者展现出不同的磷光性能和磁化率值。
[Abstract]:In this paper, the progress of aryl methyl radical functional materials and the application of protonation in organic molecules are reviewed. In our previous research work, we synthesized a stable luminescent neutral radical substrates obip and obip-CHO. On this basis, we further developed the study of functional free radical materials. Firstly, two stable diarylmethyl monradical 5 and diarylmethyl triradical 7 were designed and synthesized by a simple one-pot method. The two free radicals exhibit different properties due to their different electronic structure and stacking state. After acidizing in HC1O4 solution, 5 can be easily converted to 7. 5%. Compared with 5, 7 has higher quantum yield and higher near infrared absorption, which is due to the unique proton sharing hydrogen bond in 7. In addition, the phosphorescence, color and magnetic properties between 5 and 7 can be converted to each other under the stimulation of acid-base gas, and different EPR signals are given accordingly. Therefore, the proton sharing hydrogen bond can be used as a switch between 5 and 7: when protonated, the switch "on" 7 is stable, and the EPR exhibits a seven-fold signal peak with fluorescence properties, and when the switch "off" 7 is deprotonated, the switch "off" 7 turns into a single signal peak. The weak 7. 7 luminescence can be used as a phosphorescence sensing device for ammonia due to its ability to respond to this kind of stimulation of acid and basic gas. This work provides a new synthesis method for the study of new multifunctional materials which can change color, luminescence and magnetism reversible by external stimulation, and provides inspiration for the fabrication of new sensing devices. Secondly, on the basis of the previous chapter, we continue to cultivate a single crystal in hydrochloric acid system, which has an interesting three-ring [6.2.0.0] configuration formed by the interaction of multiple hydrogen bonds. In addition, based on the crystallographic evidence of single crystals, we report for the first time an undissociated HC1 hydrate single crystal and the unconventional cis-linear conformation of its aqueous molecular dimer. It is also proved that the unique phenomenon is caused by the ring geometry effect of the three-ring configuration. The importance of this work lies in the discovery of undissociated HC1 hydrate single crystals at room temperature and the formation of cis-linear conformation water molecular dimers without cavity binding. Our work provides assistance for exploring new configurations of HC1-H20 system at room temperature. Finally, based on the three new triarylmethyl carbon cationic radicals reported previously in the laboratory, it is found that the three triarylmethyl carbon cationic radical salts are isomers and exhibit different magnetic susceptibility values at 300K. In this chapter, a triarylmethyl carbon cationic radical (labeled TAM Cl-O) is synthesized by a simple one-pot method. Interestingly, when it is protonated, "cis" TAM Cl- is transformed into "trans" triarylmethyl carbon cationic radical (labeled HTAM2 _ 2ClO _ 4-H _ 2O). The obvious conformation change is caused by the intramolecular hydrogen bond formed by an exocyclic carbonyl oxygen atom and protonated pyridine nitrogen atom. At the same time, the change of conformation also leads to the change of crystal structure and properties. Compared with the trans-conformation HTAM2 _ 2ClO _ 4-H _ 20, the cis-conformation TAM _ (Cl-) has one dimensional high hydrophobic channel. In addition, due to the change of conformation, they exhibit different phosphorescence properties and magnetic susceptibility values.
【学位授予单位】：中国科学技术大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TB34

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