Gaining Selectivity Control in Homogeneous Catalytic Ester Formation and Reduction with Multi-Nuclear High Resolution FlowNMR Spectroscopy

这项研究最初打算看看Gusev的NNP催化剂和苯甲酸甲酯与H2还原为苯甲醇。为了确定催化循环和动力学，正在使用动态反应监测技术;特别是FlowNMR，其具有独特的能力，可以在真实的时间内发现均匀溶液化学性质的详细和定量变化，从而使用户能够识别中间物质。有了这些信息，人们可以设计理想的条件和/或催化剂，以避免抑制效应或催化剂失活。已经存在许多问题，涉及进一步了解这些钳形催化剂的机制，包括：水分的影响似乎对反应有害，与其他底物相比，乙基酯作为底物的明显优势，或被认为与催化剂有关的不饱和底物的异构化去活化FlowNMR的使用提供了一个强大的工具，可以回答这些问题和其他问题。我将建立氢化反应，同时进行实时核磁共振测量，以便计算和分析反应的化学性质。该项目的目标如下：-展示钌钳形催化剂在酯氢化中的高活性;减少传统化学计量氢化物试剂的替代，从而带来环境和经济效益。-使用动态反应监测/ 1H和31 P FlowNMR光谱详细分析，研究酯加氢和转移加氢的催化机理。确定催化剂失活的途径和原因。利用获得的反应动力学知识优化未来的反应条件和催化剂。

This research initially intends to look at Gusev's NNP catalyst and the reduction of methyl benzoate to benzyl alcohol with H2. In order to determine the catalytic cycle and kinetics, dynamic reaction monitoring techniques are being utilised; particularly FlowNMR which has the unique ability to find detailed and quantitative changes in the chemical nature of a homogeneous solution in real time and thus give the user the capability to identify intermediate species. With such information, one could design ideal conditions and/or catalysts to avoid inhibitive effects or catalyst deactivation.Already many questions exist relating to further understanding the mechanism of these pincer catalysts including: the effect of moisture which appears to be detrimental to the reaction, the apparent superiority of ethyl esters as substrates compared to others or the isomerisation of unsaturated substrates thought to be linked to catalyst deactivation. The use of FlowNMR presents a powerful tool with which these questions and others can be answered. I will be setting up hydrogenation reactions while taking live NMR measurements to allow me to calculate and analyse the chemistry of the reaction.The aims of the project are as follows:- Demonstrate high activity with Ruthenium pincer catalysts for ester hydrogenation; warranting replacement of traditional stoichiometric hydride reagents and thus bringing environmental and economic benefits.- Investigate catalytic mechanism for ester hydrogenation and transfer hydrogenation with detailed analysis using dynamic reaction monitoring / 1H and 31P FlowNMR spectroscopy.- Identify pathway and causes for catalyst deactivation.- Use acquired knowledge of reaction kinetics to optimise future reaction conditions and catalysts.