RUI: Evaluation of Ligand Effects in Molybdenum Catalyzed Deoxydehydration Reaction

RUI：钼催化脱氧脱水反应中配体效应的评价

• 批准号: 1800605
• 负责人: Alex John
• 金额: $ 24万
• 依托单位: Cal Poly Pomona Foundation, Inc.
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1800605&HistoricalAwards=false
• 关键词: RUI; Evaluation; Ligand; Effects; Molybdenum

With funding from the Chemical Catalysis Program in the Division of Chemistry, Dr. Alex John of the California State Polytechnic University Pomona (Cal Poly Pomona) is studying the use of metal catalysts that are capable of removing two adjacent OH (i.e., hydroxyl) groups from an organic substrate, and replacing them with a carbon-carbon double bond. Carbon-carbon double bonds are useful as they can be converted to a variety of other organic functional groups. Current catalysts capable of performing this transformation are based on expensive metals and are not suitable for large-scale industrial processes, while the catalysts that Dr. John is developing are based on molybdenum and are relatively inexpensive. Using a combination of experimental and computational methods, Dr. John is developing a comprehensive understanding of factors that affect catalytic activity and thereby developing superior catalysts for this transformation. The ultimate goal of this work is to convert cellulosic biomass-derived materials, which have an abundance of hydroxyl groups, including adjacent hydroxyl groups, into molecules that can be used as chemical feedstocks in order to reduce our dependence on fossil resources. This research is primarily being carried out by undergraduate students in Dr. John's laboratory, including underrepresented minorities in STEM areas. Students involved in this research gain a better understanding of the issues plaguing the global chemical industry, and they are better prepared as they enter the workforce.A key challenge plaguing the potential utilization of biomass as a sustainable chemical feedstock is its highly functionalized nature, and hence methods for efficient and selective defunctionalization of this sustainable resource are needed. The deoxydehydration reaction is ideal in this regard, as it converts glycols into olefins that are platform chemicals. Dr. John is exploring the utility of well-defined oxo-molybdenum complexes supported over modular ligands in the deoxydehydration (DODH) reaction. Oxomolybdenum complexes utilizing an array of ligands that are known to exhibit differential coordination to the oxo-molybdenum core are being synthesized and tested in this reaction to optimize catalytic activity. Viable oxo-molybdenum complexes are probed further by evaluating DODH activity as a function of ligand structure (sterics/electronics/flexibility). Mechanistic insights are gained by a combination of experimental (kinetic studies) and computational (Density Functional Theory, DFT) investigations to understand the origin of ligand effects on reactivity. Data generated and mechanistic insights gained from this study are of general interest to the broader inorganic, organometallic, and catalytic communities. The proposal is inclusive for students, especially undergraduates and minority students, with diverse backgrounds/skill levels. Students engaged in this research are developing technical skills in a variety of synthetic, characterization, and analytical techniques, and are better prepared to enter the future workforce in STEM areas.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.

通过化学催化计划的资金，加利福尼亚州理工大学Pomona（Cal Poly Pomona）的Alex John博士正在研究使用有机底物的两个相邻OH（即羟基）组的金属催化剂的使用，并用有机底物取代它们，并用碳纤维双键代替它们。碳碳双键很有用，因为它们可以转换为其他各种有机官能团。当前能够执行这种转化的催化剂基于昂贵的金属，不适合大规模的工业过程，而约翰博士开发的催化剂是基于钼的，相对便宜。约翰博士结合了实验和计算方法的结合，正在对影响催化活性的因素进行全面的理解，从而为这种转化开发了出色的催化剂。这项工作的最终目的是将纤维素生物量衍生的材料转化，这些材料具有丰富的羟基，包括相邻的羟基，将可以用作化学原料的分子，以减少我们对化石资源的依赖。这项研究主要是由约翰博士实验室的本科生进行的，其中包括STEM地区代表性不足的少数民族。参与这项研究的学生可以更好地理解困扰全球化学工业的问题，并且在进入劳动力时做好了准备。一项关键挑战困扰着将生物量作为一种可持续化学原料的潜在利用，这是其高度功能化的性质，因此需要对这种可持续的可持续资源进行有效和选择性的降级方法。在这方面，脱氧脱水反应是理想的选择，因为它将甘氨酸转化为烯烃是平台化学物质的烯烃。约翰博士正在探索在脱氧脱水（DODH）反应中模块化配体支持的明确定义的氧溶血络合物的效用。利用一系列配体的氧化胞菌合体已知与氧溶血核表现出差异配位的配体，正在合成和测试此反应中，以优化催化活性。通过评估DODH活性作为配体结构的函数（集体/电子/灵活性），进一步探测了可行的Oxo-Molybdenum复合物。机械洞察是通过实验（动力学研究）和计算（密度功能理论，DFT）研究的结合来获得的，以了解配体对反应性的影响的起源。从这项研究中获得的数据产生的和机械洞察力是广泛的无机，有机金属和催化群落的普遍兴趣。该提案对学生，特别是本科生和少数族裔学生的知识包括不同的背景/技能水平。从事这项研究的学生正在发展各种综合，表征和分析技术的技术技能，并准备更好地进入STEM领域的未来劳动力。该奖项反映了NSF的法定任务，并被认为是通过基金会的知识分子优点和更广泛的影响审查标准来评估值得通过评估来支持的。

项目成果

Additive-Free Oxidative Cleavage of a Simple Lignin Model Compound in Air using Vanadium Complexes

• DOI: 10.1007/s11244-023-01902-8
• 发表时间: 2024-02-06
• 期刊: TOPICS IN CATALYSIS
• 影响因子: 3.6
• 作者: Musharbash，Paul W.;Torres，Jerome B.;John，Alex
• 通讯作者: John，Alex

Molybdenum Catalyzed Deoxydehydration of Aliphatic Glycols Under Microwave Irradiation

• DOI: 10.1016/j.jorganchem.2023.122705
• 发表时间: 2023-04
• 期刊: Journal of Organometallic Chemistry
• 影响因子: 2.3
• 作者: P. M. Lam;A. John

Influence of the pendant arm in deoxydehydration catalyzed by dioxomolybdenum complexes supported by amine bisphenolate ligands

• DOI: 10.1039/d0nj02151b
• 发表时间: 2020-06
• 期刊: New Journal of Chemistry
• 影响因子: 3.3
• 作者: Timothy C. Siu;Israel Silva;Maiko J. Lunn;A. John