New Paradigms in Main Group Element Assembly and Catalysis

概况.主族元素在地球上非常丰富，是现代电子产品、LED和家用产品的重要组成部分。在本提案中，我们基于研究团队在基础无机化学方面的经验，解决了以下紧迫问题：a）我们能否在不需要剧毒化学品或苛刻条件的情况下，为先进的光电应用存款导电或绝缘组件？B）我们能诱导廉价的主族元素进行以前只用于昂贵金属的催化转化吗？ 我们使用碳基配体来拦截活性富氢主族物种，称为氢。它们通常以自由实体的形式出现在外来的地方，例如在星际空间或高温下。我们的工作旨在利用催化剂的反应性，在温和条件下实现无金属催化或先进材料合成。NMR、IR和UV-vis光谱用于监测反应进程，X射线晶体学用于鉴定新的分子结构。凝胶渗透色谱法和热分析（TGA/DSC）使我们能够表征聚合物，而计算方法作为重要的预测工具，以评估潜在的反应路径。我们与世界各地的专家合作，这种互动将有助于我们设计/测试新的电池和烯烃聚合催化剂。 我们提出的方案是按照沿着三个相互关联的主题分组的： 1.导体和绝缘体的轻度沉积。传统上，电活性组件已被纳入使用高温和有毒气体前体的设备中。然而，这些方法的苛刻性质限制了可以沉积的材料的类型。我们将利用各种元素的快速，基于溶液的形成（如二氢化锗（II））及其温和转化为纯元素薄膜，纳米材料和聚合物，用于下一代太阳能电池和电池。我们还将开发目前在>1500 ℃下制备的高度寻求的绝缘体氮化硼的前体。 2.用于催化的非无辜刘易斯酸性配体。我们将探索一类新的配体，结合了高度的空间覆盖率与固有的电子缺陷（刘易斯酸）基团的有利反应性。这些缺电子配体与反应性主基中心的紧密接近应鼓励合作相互作用，从而导致改进的催化活性。 3.阴离子N-杂环烯烃。我们最近制备了一系列碳基配体，称为阴离子N-杂环烯烃（aNHOs）。我们将利用aNHO的供体能力来获得一系列预先设计用作烯烃聚合催化剂的低配位主族化合物（十亿美元的产业）。这些aNHO配体还将用于解决工业中长期存在的挑战：从丰富的氮气中温和催化形成氨。

Overview. Main group elements are Earth abundant and form essential components of modern electronics, LEDs, and household products. In this proposal we build upon our research team's prior experience in fundamental inorganic chemistry to address the following pressing questions: a) Can we deposit conducting or insulating components for advanced optoelectronic applications without the need for highly toxic chemicals or harsh conditions? b) Can we coax inexpensive main group elements into performing catalytic transformations previously reserved for expensive metals? We use carbon-based ligands to intercept reactive hydrogen-rich main group species, termed hydrides. These hydrides are often found as free entities in exotic locals such as in interstellar space or at high temperatures. Our work seeks to harness the reactivity of hydrides to accomplish metal-free catalysis or advanced material synthesis under mild conditions. NMR, IR and UV-vis spectroscopy are used to monitor reaction progress and X-ray crystallography to identify new molecular structures. Gel permeation chromatography and thermal analyses (TGA/DSC) allow us to characterize polymers, while computational methods serve as vital predictive tools to evaluate potential reaction paths. We collaborate with experts worldwide and such interactions will help us design/test new batteries and olefin polymerization catalysts. Our proposed program is grouped along three interconnected themes: 1. Mild Deposition of Conductors and Insulators. Traditionally electroactive components have been incorporated into devices using high-temperatures and toxic gaseous precursors. However the harsh nature of these methods places a limit on the types of materials that can be deposited. We will take advantage of the rapid, solution-based, formation of various element hydrides (such as germanium(II) dihydride) and their mild conversion into pure element films, nanomaterials and polymers for use in next generation solar cells and batteries. We will also develop precursors to the highly sought insulator boron nitride, currently prepared at >1500 C. 2. Non-innocent Lewis Acidic Ligands for Catalysis. We will explore a new class of ligand that combines a high degree of steric coverage with the advantageous reactivity inherent to electron deficient (Lewis acidic) groups. The close proximity of these electron deficient ligands to reactive main group centers should encourage cooperative interactions, leading to improved catalytic activity. 3. Anionic N-Heterocyclic Olefins. We recently prepared a series of carbon-based ligands termed anionic N-heterocyclic olefins (aNHOs). We will harness the donor ability of aNHOs to access a series of low-coordinate main group compounds that are pre-designed to act as olefin polymerization catalysts (a billion dollar industry). These aNHO ligands will also be used to tackle a long-standing challenge in industry: the mild catalytic formation of ammonia from abundant nitrogen gas.