Carbonyl Coupling Reactions Probe Oxide Surfaces

羰基偶联反应探针氧化物表面

• 批准号: 9100404
• 负责人: Mark Barteau
• 金额: $ 28万
• 依托单位: University of Delaware
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1991
• 资助国家: 美国
• 起止时间: 1991-04-01 至 1994-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9100404&HistoricalAwards=false
• 关键词: Carbonyl; Coupling; Reactions; Probe; Oxide

This research examines the active site requirements for carbonyl coupling reactions on titania surfaces. The goals are to identify the active sites for ketonization of carboxylic acids, aldol condensation, and carbonyl metathesis, and to develop these reactions as probes of the chemical and physical properties of metal oxides. The influence of surface structure on reactivity is examined on both stable and metastable oxide surfaces. New oligomerization reactions that can be carried out even under ultrahigh vacuum are explored, thereby demonstrating the application of surface-science approaches, including electron and ion spectroscopies, to oligomerization, polymerization, and metathesis catalysts. Site requirements for intramolecular coupling reactions analogous to observed intermolecular reactions are probed using difunctional carboxylic acids, alcohols, and aldehydes. Structures of reactive surfaces and associated adsorbates are imaged by scanning tunneling microscopy. Although this effort addresses fundamental questions, it should improve understanding of many important industrial processes, ranging from Ziegler-Natta polymerization (used to make polyethylene and polypropylene) to the synthesis of complex biomolecules. The results could also have a major impact on the design of sensor and separation devices.

本研究考察了二氧化钛表面羰基偶联反应的活性位点要求。目的是确定羧酸酮化，醛醇缩合和羰基复分解的活性位点，并将这些反应作为金属氧化物化学和物理性质的探针。在稳定和亚稳氧化表面上考察了表面结构对反应性的影响。探索了甚至在超高真空下也能进行的新的低聚反应，从而展示了表面科学方法，包括电子和离子光谱，在低聚、聚合和复分解催化剂上的应用。分子内偶联反应的位置要求类似于观察到的分子间反应，用双官能团羧酸、醇和醛来探测。用扫描隧道显微镜对反应表面和相关吸附物的结构进行成像。虽然这一努力解决了基本问题，但它应该提高对许多重要工业过程的理解，从齐格勒-纳塔聚合（用于制造聚乙烯和聚丙烯）到复杂生物分子的合成。研究结果也可能对传感器和分离装置的设计产生重大影响。