New Reaction Chemistry with Transition Metal Complexes for Conversion of Oxygenated

在化学系化学合成项目的资助下，加州理工学院的Theodor Agapie博士正在合成分子化合物，以研究以一氧化碳（CO）为原料生产液体燃料。液体燃料（如甲醇和乙醇）是特别可取的，因为它们使美国经济维持其目前的能源基础设施。虽然已知将CO转化为含有碳-碳键的燃料的催化剂，但它们的反应在化学上具有挑战性，而且人们对其知之甚少。Agapie博士的催化剂能够形成含有理想碳-碳键的产物，使用CO作为起始材料。他还利用这些化合物系统地研究它们的结构和反应性之间的关系，以便对控制它们行为的原理有一个基本的了解。这些进步帮助美国保持在能源经济的前沿。Agapie小组参与了与加州帕萨迪纳市高中生的外展活动。他们支持加州理工学院的课堂联系，发展与马歇尔基础高中教师的关系。高中学生的访问和科学职业研讨会吸引了学生从事STEM职业。本科生参与加州理工学院的安进和WAVE项目，这些项目的目标是为科学领域代表性不足的学生提供研究机会，促进他们的科学事业。除了技术培训外，研究生还通过与本科生一起工作来培养他们的指导技能，为培养有才能的劳动力做出贡献。Agapie博士正在系统地研究一系列钼配合物的结构-反应性关系，以便对控制CO和CO2的还原偶联选择性和脱氧的设计原则有一个基本的理解。显示存储电子和改变配位模式能力的配体结构正在制备中。机制和配体设计假设进行了测试，以确定供体性质、配体稳定性、还原电位和亲电试剂对CO裂解和偶联反应结果的影响。使用温和的试剂，这是实际应用所必需的，是有针对性的。正在解决的具体挑战包括：1)确定配体对CO裂解产生金属碳化物的影响；2)确定控制CO一致性程度的结构特征（C2 vs C3等）；3)确定在温和条件下（H+, H-, H2）从观察到的中间体生成Cn （n大于或等于2）产物的途径；4)评价与实际应用相关的试剂，如质子亲电试剂，氢化物和H2作为质子和电子的来源。这些研究可能为设计廉价和实用的催化剂以将碳原料升级为高价值的化学品和燃料提供必要的基础知识。该项目由本科生和研究生进行，使他们接触到几个技术领域，包括合成、光谱学和机械研究，所有这些都有助于培养训练有素的劳动力。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

With funding from the Chemical Synthesis Program of the Division of Chemistry, Dr. Theodor Agapie of the California Institute of Technology is synthesizing molecular compounds to study the production of liquid fuels from carbon monoxide (CO) as a starting material. Liquid fuels (such as methanol and ethanol) are particularly desirable as they allow the U.S. economy to maintain its current energy infrastructure. While catalysts for the conversion of CO to fuels containing carbon-carbon bonds are known, their reactions are chemically challenging and poorly understood. Dr. Agapie's catalysts are capable of forming products containing the desirable carbon-carbon bonds using CO as a starting material. He is also using these compounds to systematically study the relationship between their structure and reactivity in order to develop a fundamental understanding of the principles controlling their behavior. Such advances help the US stay at the forefront of the energy economy. The Agapie group is involved in outreach activities with high school students in Pasadena, CA. They support the Caltech Classroom Connection, developing relationships with teachers as Marshall Fundamental High School. The visits by high school students and workshops on careers in science have engage students in STEM careers. Undergraduate students participate in the projects under Caltech programs Amgen and WAVE which have the goal of providing research opportunities to facilitate careers in science by students who are underrepresented in science. In addition to technical training, graduate students develop their mentorship skills by working with undergraduates, contributing to the education of a talented workforce. Dr. Agapie is systematically studying structure-reactivity relations of a family of molybdenum complexes in order to develop a fundamental understanding of the design principles controlling the selectivity of reductive coupling and deoxygenation of CO and CO2. Ligand architectures that display the ability to store electrons and change coordination modes are being prepared. Mechanistic and ligand design hypotheses are tested to determine the effect of the nature of donors, ligand lability, reduction potential, and electrophiles on the outcome of CO cleavage and coupling reactions. The use of mild reagents, which is necessary for practical applications, is targeted. Specific challenges that are being addressed include: 1) Determination of ligand effects on the cleavage of CO, to generate a metal carbide; 2) Determination of structural features controlling the extent of CO homologation (C2 vs C3, etc); 3) Determination of pathways for Cn (n greater than or equal to 2) product generation from observed intermediates using mild conditions (H+, H-, H2); 4) Evaluation of reagents that are relevant to practical applications such as protons as electrophiles, and hydride and H2 as sources of protons and electrons. These studies may provide the fundamental knowledge necessary for the design of inexpensive and practical catalysts for upgrading of carbon feedstocks to higher value chemicals and fuels. This project is being conducted by undergraduate and graduate students and is exposing them to several technical areas, including synthesis, spectroscopy, and mechanistic studies, all of which facilitate the development of a well-trained workforce.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.