Small molecule activation and sensing

拟议的研究计划侧重于小分子的激活和检测。第一个目标是从根本上开发新的绿色方法来捕获二氧化碳，二氧化碳是一种强有力的温室气体和所有化石燃料燃烧产生的碳废物，并将其用作可持续的单碳原料，以制备增值有机产品。2013年，我们团队开发了一系列化合物(包括一种不含金属的化合物)，这些化合物可以选择性地打破它们自己的碳氢键之一，并在其间储存一个二氧化碳分子。我们将应用从最近这一突破中获得的知识来设计新的系统，这种系统可以选择性地打破其他类型的键，并在其间储存二氧化碳。此外，我们还将开发催化过程，将储存的二氧化碳转化为具有重要工业应用的有机化合物(如甲酸盐)。第二个目标是解开大自然如何将大气中的氮素转化为氨的谜团，并学习如何直接从氮素中制造其他氮化合物。我们将制备结构上与固氮酶(天然将氮素转化为氨的酶)的活性部位相似的新型铁化合物，并研究这些化合物对氮素的反应活性，以推断固氮酶的行为。固氮酶活性的一个令人费解的特征是，当氮与活性部位的铁中心结合时，会损失二氢。2010年，我们的团队在氮气下加热Ru(元素周期表中仅次于铁的元素)化合物时，观察到了类似的反应活性，即DNN与Ru中心结合，伴随着氢气的损失。在这个类比的启发下，我们将进一步探索Ru结合的氮的反应性，这可能为深入了解金属结合的氮的反应模式提供帮助。从这项研究中获得的信息将有助于阐明大自然如何将氮气转化为氨，并帮助我们利用氮气的反应性，从空气中大量的氮气中直接合成含氮的有机化合物。第三个目标是设计用于检测生态毒素的发光传感器。2013年，我们团队开发了一种用于DMF蒸气的选择性传感器，该传感器负责皮革和合成纤维工厂的几个职业健康问题，并研究了其潜在机制。我们将把这些知识应用到检测硝酸盐和甲醛的传感器的设计中；前者是一种在世界各地城市家庭和家具中普遍存在的有害化学物质，而后者是过度使用化肥造成的饮用水中的污染物。我们还将努力将我们的传感器设计原则推广到对其他与环境有关的化学品的传感。这一成功的成果将使便携式传感器能够方便地检测空气和水中的污染物。所有这些项目都对环境产生了积极影响，并有助于在基础和实际层面上促进知识的发展。

The proposed research program is focused on the activation and detection of small molecules. The first objective is to develop fundamentally new and green ways to capture carbon dioxide, which is a potent greenhouse gas and carbon waste from the combustion of all fossil fuels, and to utilize it as sustainable one-carbon feedstock to prepare value-added organic products. In 2013, our group developed a series of compounds (including a metal-free one), which can selectively break one of their own carbon-hydrogen bonds and store one molecule of carbon dioxide in between. We will apply the knowledge gained from this recent breakthrough to design new systems that can selectively break other types of bonds and store carbon dioxide in between. Moreover, we will develop catalytic processes to convert the stored carbon dioxide into organic compounds (such as formate) which have important industrial applications. The second objective is to solve the mystery of how nature converts atmospheric dinitrogen into ammonia and to learn how to make other nitrogen compounds directly from dinitrogen. We will prepare novel iron compounds that structurally resemble the active site of nitrogenase (nature’s enzyme that converts dinitrogen into ammonia) and investigate the reactivity of these compounds toward dinitrogen to deduce the nitrogenase behaviours. One puzzling feature of the nitrogenase activity is the loss of dihydrogen upon dinitrogen binding on an iron centre at the active site. In 2010, our group observed an analogous reactivity when heating a ruthenium (the element right below iron in the periodic table) compound under dinitrogen, i.e., dinitrogen binds with the ruthenium centre with concomitant loss of dihydrogen. Prompted by this analogy, we will further explore the reactivity of the ruthenium-bound dinitrogen, which may provide insight into the reactivity patterns of metal-bound dinitrogen. Information gained from this research will shed light on how nature converts dinitrogen into ammonia and help us harness dinitrogen reactivity to make nitrogen-containing organic compounds directly from the abundant dinitrogen gas from air. The third objective is to design luminescent sensors for detecting ecotoxins. In 2013, our group developed a selective sensor for DMF vapor, which is responsible for several occupational health problems at leather and synthetic fibre factories, and studied the underlying mechanism. We will apply this knowledge to the design of sensors for detecting nitrate and formaldehyde; the former is a prevalent harmful chemical found worldwide in urban homes and furniture, while the latter is a pollutant in drinking water caused by the overuse of fertilizers. Efforts will also be made to generalize the principle of our sensor design toward the sensing of other environmentally concerned chemicals. The successful outcome will result in portable sensors for the facile detection of pollutants in air and water. All these projects have positive environmental impacts, and contribute to the advancement of knowledge at both fundamental and practical levels.