New Paradigms in Main Group Element Assembly and Catalysis

概述。主族元素是富含稀土的元素，构成现代电子产品、LED和家居产品的基本组件。在这项建议中，我们以研究团队在基础无机化学方面的先前经验为基础，解决以下紧迫问题：a)我们能否在不需要剧毒化学品或恶劣条件的情况下，为先进的光电应用沉积导电或绝缘元件？B)我们能否诱使廉价的主族元素进行以前专为贵金属保留的催化转化？我们使用碳基配体来拦截反应性的富氢主族物种，称为氢化物。这些氢化物经常以自由实体的形式在奇异的地方被发现，例如在星际空间或在高温下。我们的工作旨在利用氢化物的反应性在温和的条件下完成无金属催化或先进材料合成。用核磁共振、红外光谱和紫外可见光谱监测反应进程，用X射线结晶学鉴定新的分子结构。凝胶渗透色谱和热分析(TGA/DSC)使我们能够表征聚合物，而计算方法则是评估潜在反应路径的重要预测工具。我们与世界各地的专家合作，这种互动将帮助我们设计/测试新的电池和烯烃聚合催化剂。我们建议的方案分为三个相互关联的主题：1.导体和绝缘体的温和沉积。传统上，电活性元件被结合到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。我们将利用基于溶液的快速形成各种元素氢化物(如Ge(II)二氢化合物)的优势，并将它们温和地转化为纯元素薄膜、纳米材料和聚合物，用于下一代太阳能电池和电池。我们还将开发备受关注的绝缘体氮化硼的前体，目前在&gt；1500°C.2.用于催化的非无害刘易斯酸性配体。我们将探索一类新的配体，它结合了高空间覆盖率和电子缺乏(Lewis酸性)基团固有的有利反应活性。这些缺乏电子的配体靠近活性主基中心，应该会促进协同作用，从而提高催化活性。3.阴离子N-杂环烯烃。我们最近合成了一系列碳基配体，称为阴离子N-杂环烯(ANHO)。我们将利用aNHO的给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(10亿美元的行业)。这些ANHO配体还将用于解决工业中的一个长期挑战：从丰富的氮气中温和催化生成氨。

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.