Synthetic Phosphorus Chemistry: The Systematic Development of Organophosphorus Molecules and Polymers

本文提出的研究旨在系统地发展磷及其化合物的化学性质。磷是一种重要的元素，不仅是生命所必需的，而且被用于大量的商业产品中。我们工作的主要目标是开发含有磷作为主链关键成分的聚合物。一种特定聚合物的性质和潜在应用是构成其链结构的原子的排列和类型的直接结果。目前使用的大多数聚合物是由含有碳、氧和/或氮原子的链按明确的顺序组成的。由其他元素组成的聚合物的发展还处于起步阶段，然而，由于这些所谓的无机聚合物独特的物理性质和化学功能，它们有相当大的前景。例如，商业聚合物硅，由硅和氧原子交替组成，具有有机聚合物无法达到的极端柔韧性和温度稳定性。无机聚合物发展的关键挑战是缺乏将无机元素纳入长链的通用合成路线。

The research proposed herein aims to systematically develop the chemistry of phosphorus and its compounds. Phosphorus is an important element, not only being essential for life but being used in a wealth of commercial products. The primary objective of our work is to develop polymers that contain phosphorus as a key component of the main chain. The properties and potential applications of a particular polymer are a direct consequence of the arrangement and type of atoms that make up the chain structure. Most polymers in use today are comprised of chains containing carbon, oxygen, and/or nitrogen atoms in well-defined sequences. The development of polymers composed of other elements is at its infancy, however, there is considerable promise for these so-called inorganic polymers due to their unique physical properties and chemical functionality. For example, the commercial polymer silicone, consisting of alternating silicon and oxygen atoms, has extreme flexibility and temperature stability that is unattainable with organic polymers. The key challenge to inorganic polymer development is the lack of general synthetic routes to incorporate inorganic elements into long chains. The addition polymerization of the C=C bond of olefins is perhaps the most important method of industrial polymer production being used to make polyethylene, polypropylene polystyrene, acrylics, and Teflon, to name a few. It was long believed that heteroatom-containing multiple bonds were not suited for addition polymerization methods. We have shown that the addition polymerization of the P=C bond in a phosphaalkene is a route to phosphorus-containing polymers. This is a subject that will be rigorously pursued during the next five years. The mechanism of this new polymerization reaction is still in question and our proposed investigations are outlined herein. We will also explore the synthesis of chiral phosphaalkenes that may be employed directly as ligands for transition metal-catalysis and small-molecule activation or as monomers to afford polymeric ligands for use in polymer-supported catalysis. In a final area of pursuit, we propose to develop new types of p-conjugated phosphorus-containing polymers that exploit the chemical functionality of phosphorus as a means to tailor the electronic properties for application in areas such as small molecule sensor materials. In closing, the work proposed herein further expands the fascinating chemistry of phosphorus. This work will lead to gains in fundamental knowledge of inorganic chemistry and polymer science, and will provide a foundation for future technological applications.