Travel Grant: Aqueous Oxidation of Methanol by V-Containing Biocatalysts

[57968]鉴于人们对无机负载型氧化钒催化剂上甲醇氧化的基本认识相对于含v酶而言较为先进，目前将氧化钒无机催化剂研究中发展起来的原位和操作多方法应用于含钒生物无机酶催化剂的研究是一个很好的研究机会。具体来说，在水氧化反应中使用最先进的原位时间分辨和操作光谱方法（拉曼，UV-vis, ATR-IR， 51V NMR和quick-XANES/EXAFS）建立了含钒酶氧化甲醇的基本结构-活性关系。该研究项目的成功得益于与中东技术大学（土耳其安卡拉）的Onal教授的研究小组的合作，他是密度泛函理论计算的领导者。与Onal教授的合作是最近由NSF支持的第六届东地中海化学工程会议的成果。知识价值。本研究的目的是：(1)建立有效的表征方法和方法，用于研究HOOH和CH3OH环境下水相氧化钒催化剂的原位时间分辨和操作光谱研究（拉曼、UV-vis、51V核磁共振、EPR、快速扫描ATR-IR和快速xanes /EXAFS）；(2)应用先进的方法研究VOx结构、氧化态、反应中间体、均相钒卤化过氧化物酶作为甲醇水相氧化生物催化剂的机理和动力学。目前，前沿催化研究必须将最新的分子光谱表征方法与最先进的密度泛函理论（DFT）相结合。水溶液中相当复杂的含V酶具有多种氧官能团（如末端V=O键、V-O- h键、桥接V-O- c键和过氧V- o2键），如果没有DFT计算的帮助，这些氧官能团的振动分配并不直接。建议与中东技术大学（土耳其Anakara）的Onal教授小组合作对含v酶进行DFT计算，因为只有这样的研究才能提供对不同反应途径的反应能量学的分子水平的见解。只有结合分子光谱的见解与反应途径，才能实现分子结构反应性关系，这是本研究计划的最终目标。更广泛的影响。提出的研究项目将以往的气固CH3OH氧化催化研究扩展到CH3OH的液相氧化，并将无机催化与酶的水生物无机催化连接起来。研究无机和生物无机催化剂的水相催化的时间分辨原位和操作光谱方法的发展得到了显著的推进，并对许多水相催化应用具有广泛的意义。钒生物无机酶可能为目前氧化反应中使用的传统无机催化剂提供一种“绿色”替代品，新的基本见解可能有助于改进药物、治疗、糖尿病管理和生物催化工业应用的发展。利哈伊小组明显受益于一个领先的研究小组进行密度泛函理论计算的接触和训练。土耳其集团通过接触最先进的实验光谱催化剂表征方法和理论与实验的整合显着受益。

1057968WachsIn light of the relative advanced fundamental understanding of methanol oxidation over inorganic supported vanadium oxide catalysts relative to V-containing enzymes, there is currently an excellent research opportunity to apply the in situ and operando methodologies developed in the study of vanadium oxide inorganic catalysts to the study of vanadium containing bioinorganic enzyme catalysts. Specifically, the employment of state-of-the-art time resolved in situ and operando spectroscopic methods (Raman, UV-vis, ATR-IR, 51V NMR and quick-XANES/EXAFS) during aqueous oxidation reactions establish the fundamental structure-activity relationships for methanol oxidation by vanadium-containing enzymes. The success of this research program is greatly enhanced by collaboration with the research group of Professor Onal at Middle Eastern technical University (Ankara, Turkey), a leader in density functional theory calculations. The collaboration with Professor Onal is an outgrowth of the recent 6th Eastern Mediterranean Chemical Engineering Conference that was supported by NSF.Intellectual Merit. The objectives of this research are to (1) establish effective characterization methods and approaches for the study vanadium oxide catalysts in the aqueous phase in the presence of HOOH and CH3OH environments with time resolved in situ and operando spectroscopy studies in the millisecond to minutes time scale (Raman, UV-vis, 51V NMR, EPR, rapid scan ATR-IR and quick-XANES/EXAFS) and (2) apply the advanced methodologies to study the VOx structures, oxidation states, reaction intermediates, mechanism, and kinetics of homogeneous vanadium haloperoxidase as a biocatalyst for the aqueous phase oxidation of methanol. Today, cutting edge catalysis research must combine the latest molecular spectroscopic characterization methodologies under relevant reaction conditions with state-of-the-art density functional theory (DFT). The rather complex V-containing enzymes in aqueous solution possess multiple oxygen functionalities (e.g., terminal V=O bonds, V-O-H bonds, bridging V-O-C bonds and peroxy V-O2 bonds) whose vibrational assignments are not straightforward without the assistance of DFT calculations. It is proposed that DFT calculations are performed on the V-containing enzymes in collaboration with Professor Onal's group at Middle Eastern Technical University (Anakara, Turkey) since only such research will provide molecular level insights into the reaction energetics of the different reaction pathways. Only combination of the molecular spectroscopic insights with the reaction pathways will allow the achievement of molecular structure reactivity relationships that is the ultimate goal of this research program.Broader Impact. The proposed research program extends the previous gas-solid CH3OH oxidation catalysis studies to liquid phase oxidation of CH3OH and also bridges inorganic catalysis with aqueous bioinorganic catalysis of enzymes. The development of time-resolved in situ and operando spectroscopic methodologies for investigating aqueous phase catalysis of inorganic and bioinorganic catalysts are significantly advanced by this undertaking and have wide reaching implications for numerous aqueous phase catalytic applications. Vanadium bioinorganic enzymes may provide a "green" alternative to traditional inorganic catalysts currently used in oxidation reactions and the new fundamental insights may assist in the development of improved pharmaceuticals, therapeutics, diabetes management and biocatalytic industrial applications. The Lehigh group significantly benefits from exposure to and training by a leading research group performing density functional theory calculations. The Turkish group significantly benefits by exposure to state-of-the-art experimental spectroscopic catalyst characterization methods and integration of theory with experiment.