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首页> 外文学位 >Design, synthesis, and structure-property relationship study of shape-persistent phenylene vinylene macrocycles and porphyrin-based molecular cages through dynamic covalent chemistry.
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Design, synthesis, and structure-property relationship study of shape-persistent phenylene vinylene macrocycles and porphyrin-based molecular cages through dynamic covalent chemistry.

机译：通过动态共价化学研究形状持久的亚苯基亚乙烯基大环化合物和卟啉基分子笼的设计，合成和结构性质关系。

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摘要

The objectives of the work described in this thesis are the design and synthesis of shape-persistent phenylene vinylene macrocycles (PVMs) and covalent organic polyhedrons (COPs) using dynamic covalent chemistry (DCvC); and the study of their applications in host-guest chemistry, light harvesting, gas adsorption and separation. DCvC has achieved tremendous progress during the past decade, and its application in constructing complex molecular architectures has attracted increasing attention. Conventional design and preparation of purely organic covalent architectures through irreversible bond formation usually requires multi-step synthesis and is very time consuming and low-yielding. DCvC exhibits a significant advantage: the reversible nature of the bond formation in DCvC ("self-correction"-enabled) allows the most thermodynamically stable product to be produced predominantly in one step from readily accessible precursors.;DCvC has been applied in constructing macrocyclic compounds for decades. Moore and coworkers have applied alkyne metathesis in constructing shape-persistent arylene ethynylene macrocycles. Such macrocyclic compounds showed interesting stacking properties for solid-state engineering.;Shape-persistent COPs with well-defined intrinsic cavities have been a research focus due to their unique structure features such as customizable geometry and isolated cavities. Moreover, constructed only through robust covalent bonds, the COPs usually have much higher chemical and thermal stability than their supramolecular analogues.;Further study beyond COPs involves incorporating COPs into frameworks to construct COFs. In this case, we can have individual well-defined built-in COPs in the frameworks, which are expected to be highly porous and be great candidate materials for gas adsorption, molecular separation, catalysis, chemical sensing and drug delivery.;Currently, there are still some limiting factors that impede the COP synthesis through DCvC, and the most critical issue is that the dynamic covalent bonds formed are usually labile and cannot survive harsh conditions. Our research goals are to develop novel DCvC methods utilizing more robust dynamic covalent bonds, and to construct shape-persistent molecular cages using such DCvC methods.;In Chapter 1, an overview is given of the current (state-of-art) development and applications of covalent organic cage molecules. The advantages of the DCvC approach will be highlighted.;In Chapter 2 the synthesis and aggregation study of shape-persistent phenylene vinylene macrocycles (PVMs) are described. With substitution groups varied, the PVMs exhibit very different aggregation behaviors, which help us to understand the structure-property relationship of this class of compounds.;In Chapter 3, a porphyrin-based molecular prism is described, which is the first shape-persistent organic molecular cage prepared via alkyne metathesis. More interestingly, the cage compound is able to selectively bind C70 over C60, (KC70/KC60 >1000), thus showing great potential for fullerene separation applications.;In Chapter 4, the formation of a ternary nanohybrid system consisting of the porphyrin-based molecular prism, fullerenes, and single-walled carbon nanotubes (SWCNTs) is described. A prototype device fabricated from this nanohybrid material gave decent photoconversion efficiency.;In Chapter 5, the synthesis of a porphyrin-based macrocycle is detailed. Unlike the 4-arm molecular cage reported in Chapter 4, this 2-arm macrocycle shows a highly adaptive cavity size and gives highest binding affinity for the larger fullerenes, i.e. C84.;Chapter 6 focuses on perspectives and recommended future work based on current research progress. The construction of organic cage frameworks (OCFs) from covalent polyhedron molecules was pursued. Given the large intrinsic cavities of the molecular polyhedrons, the designed OCFs are anticipated to have large cavities and be highly porous. Moreover, since the COPs have shown very strong binding affinity for fullerenes, the designed OCFs can be used for capturing as well as separating fullerenes.
机译：本文描述的工作目标是使用动态共价化学（DCvC）设计和合成形状持久性亚苯基亚乙烯基大环（PVM）和共价有机多面体（COP）。以及它们在客体化学，光收集，气体吸附和分离中的应用的研究。在过去的十年中，DCvC取得了长足的进步，其在构建复杂分子结构中的应用引起了越来越多的关注。通过不可逆键形成的常规设计和纯有机共价结构的制备通常需要多步合成，并且非常耗时且产率低。 DCvC显示出显着的优势：DCvC中键形成的可逆性质（启用“自我校正”）使主要是由易于获得的前体一步生成最热力学稳定的产物。DCvC已用于构建大环几十年来。 Moore和他的同事在构建形状持久的亚芳基亚乙炔基大环化合物中应用了炔烃复分解。这种大环化合物对固态工程显示出令人感兴趣的堆积特性。具有明确的固有腔的形状持久COP由于其独特的结构特征（例如可定制的几何形状和隔离的腔）而成为研究重点。此外，仅通过坚固的共价键构建的COP通常比其超分子类似物具有更高的化学和热稳定性。COP以外的进一步研究涉及将COP纳入框架以构建COF。在这种情况下，我们可以在框架中具有单独定义的内置COP，这些COP期望是高度多孔的，并且是气体吸附，分子分离，催化，化学传感和药物输送的理想候选材料。还有一些限制因素阻碍了通过DCvC进行COP合成，最关键的问题是所形成的动态共价键通常不稳定，无法在恶劣条件下生存。我们的研究目标是开发利用更牢固的动态共价键的新颖DCvC方法，并使用此类DCvC方法构建形状持久的分子笼。;在第一章中，概述了当前（最新）的开发和共价有机笼分子的应用DCvC方法的优点将得到重点介绍。在第二章中，描述了形状持久性亚苯基亚乙烯基大环（PVM）的合成和聚集研究。随着取代基的变化，PVM表现出截然不同的聚集行为，这有助于我们理解这类化合物的结构-性质关系。在第三章中，描述了基于卟啉的分子棱柱，这是第一个形状持久的通过炔烃复分解制备的有机分子笼。更有趣的是，笼型化合物能够选择性地将C70与C60结合（KC70 / KC60> 1000），从而显示出富勒烯分离应用的巨大潜力。;在第四章中，形成了由基于卟啉的三元纳米杂化体系描述了分子棱镜，富勒烯和单壁碳纳米管（SWCNT）。用这种纳米杂化材料制成的原型设备具有不错的光转换效率。在第5章中，详细介绍了基于卟啉的大环化合物的合成。与第4章中报道的4臂分子笼不同，该2臂大环具有高度适应性的空腔尺寸，并且对较大的富勒烯（即C84）具有最高的结合亲和力;;第6章着重介绍了观点并根据当前研究成果推荐了未来的工作进展。追求从共价多面体分子的有机笼框架（OCFs）的建设。考虑到分子多面体的固有腔较大，预计设计的OCF具有较大的腔并且是高度多孔的。此外，由于COP对富勒烯显示出非常强的结合亲和力，因此设计的OCF可以用于捕获和分离富勒烯。

著录项

  • 作者

    Zhang, Chenxi.;

  • 作者单位

    University of Colorado at Boulder.;

  • 授予单位 University of Colorado at Boulder.;
  • 学科 Chemistry Molecular.;Engineering Materials Science.
  • 学位 Ph.D.
  • 年度 2014
  • 页码 181 p.
  • 总页数 181
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

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