Electrophilic Attack on Coordinated Ligands Involved in Catalysis by Organometallic Complexes

有机金属配合物对参与催化的配位配体的亲电攻击

• 批准号: 0451385
• 负责人: Jack Norton
• 金额: $ 58.5万
• 依托单位: Columbia University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-02-15 至 2008-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0451385&HistoricalAwards=false
• 关键词: Electrophilic; Attack; Coordinated; Ligands; Involved

Dr. Jack Norton, Department of Chemistry, Columbia University, is supported by the Inorganic, Bioinorganic, and Organometallic Chemistry Program of the Chemistry Division for mechanistic studies into organometallic catalysis that involves electrophilic attack on coordinated ligands. Specific objectives include: (1) developing an effective catalyst for asymmetric C=N hydrogenation by an ionic mechanism; (2) explaining how coordinated tertiary amines (the products of C=N hydrogenation) can exchange with the corresponding free amines more rapidly than they dissociate; (3) developing an effective catalyst for the hydrogenation of aziridines and epoxides to straight-chain amines and alcohols; (4) measuring the barriers to enantiomer interconversion for imines, aldehydes, and ketones that are coordinated to electropositive metals; (5) determining if the binding of additional ligands to "constrained geometry" zirconaaziridines is stronger than to zirconocene systems. In connection with (2), a hypothesis that electron transfer initiates anomalously fast tertiary amine exchanges will be tested. In connection with (3), a hypothesis that the regiochemistry of hydride transfer depends upon whether it happens in one-step or in two (i.e., whether electron transfer and hydrogen atom transfer happen simultaneously or consecutively) will be tested.This project addresses issues that have broad important to inorganic chemistry and to organic synthesis. The project will develop new catalytic methodologies for the preparation of species that are important in, e.g., pharmaceutical chemistry. In addition, it will uncover details of how present catalysts operate. Another important goal of the project is the training of undergraduate, graduate, and postdoctoral students for industrial and academic positions. There is also an international component to the project because of a regular interchange of students between the PI's group and that of Prof. G. Erker (Muenster Germany).

哥伦比亚大学化学系的Jack Norton博士得到化学系无机、生物无机和有机化学项目的支持，从事涉及配位配体亲电攻击的有机金属催化的机理研究。具体目标包括：（1）开发了一种有效的离子机理不对称C=N加氢催化剂;（2）解释了配位叔胺C=N加氢产物与相应的游离胺的交换速度比它们解离的速度快;（3）开发一种有效的催化剂，用于氮丙啶和环氧化物加氢为直链胺和醇;（4）测量与正电性金属配位的亚胺、醛和酮的对映体互变的障碍;（5）确定附加配体与“受限几何形状”的锆氮杂环丙烷的结合是否强于与二茂锆体系的结合。关于（2），将检验电子转移引发异常快速的叔胺交换的假设。关于（3），氢化物转移的区域化学取决于它是一步还是两步发生（即，电子转移和氢原子转移是同时发生还是连续发生）。2本项目将讨论对无机化学和有机合成具有广泛重要意义的问题。该项目将开发新的催化方法，用于制备重要的物种，例如，药物化学此外，它还将揭示现有催化剂如何运作的细节。该项目的另一个重要目标是为工业和学术职位培训本科生、研究生和博士后。该项目也有一个国际组成部分，因为PI的小组和G教授的小组之间定期交换学生。Erker（明斯特德国）。