RUI: Mechanisms of C-F and S-F Bond Activation and Cross-coupling with Bidentate N-heterocyclic Carbene Nickel Catalysts

在这个RUI项目中，在化学部化学结构、动力学和机理B计划的支持下，加州州立理工大学化学系的S.Chantal E.Stieber正在研究富含地球的镍催化剂，用于将氟安装到未来可能用于成像和制药的分子上。这项工作的目标是确定镍催化剂的结构如何影响与碳-氟和硫-氟键的反应活性，以及由此产生的催化性能。这项工作包括对主要是本科院校的学生进行高级有机金属、有机和无机研究培训。这笔赠款还将用于支付夏季研究培训职位、开发新的研究教程视频，以及主办不同的研讨会演讲者。这些努力加在一起，将扩大对科学的参与，并在一家资源不足的拉美裔服务机构提供劳动力培训。用于碳-氟和硫-氟活化的镍体系还没有得到广泛的探索，但有可能为19F标记、硅烷化和硼化提供在分子上安装氟的新途径。这项工作将探索镍在芳基氟化物和磺酰氟化物中对碳-氟和硫-氟键的基本反应活性随配体环境的变化以及由此产生的交叉偶联反应的影响。合成了一系列双齿N-杂环卡宾(NHC)镍配合物，以回答以下问题：(I)配体和底物如何影响镍上碳-氟或硫-氟键的顺式和反式氧化加成？(Ii)镍上碳-氟和硫-氟键的顺式和反式氧化加成是否影响硅基化和硼化催化的交叉偶联反应？和(Iii)与芳基氟化物相比，镍与磺酰氟化物如何反应？这些研究预计将提供有关在Ni-NHC络合物上为C-F和S-F键激活赋予最大反应性的结构特征的基本信息。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

In this RUI project, with support from the Chemical Structure, Dynamics & Mechanisms-B Program of the Chemistry Division, S. Chantal E. Stieber of the Department of Chemistry at California State Polytechnic University, Pomona is studying earth-abundant nickel catalysts for installing fluorine onto molecules with potential for future use in imaging and pharmaceuticals. The goal of this work is to determine how the structure of the nickel catalyst affects the reactivity with carbon-fluorine and sulfur-fluorine bonds, and the resulting catalytic performance. This work involves advanced organometallic, organic, and inorganic research training for students at a primarily undergraduate institution. This grant will additionally support paid summer research training positions, development of new research tutorial videos, and hosting diverse seminar speakers. Combined, these efforts will broaden participation in science and provide workforce training at an under-resourced Hispanic-serving institution. Nickel systems for carbon-fluorine and sulfur-fluorine activation are not widely explored, but have the potential to provide new routes for installing fluorine on molecules for 19F labeling, silylation, and borylation. This work will probe the fundamental reactivity of nickel toward carbon-fluorine and sulfur-fluorine bonds in aryl fluorides and sulfonyl fluorides as a function of the ligand environment and resulting effects on cross-coupling reactions. A series of bidentate N-heterocyclic carbene (NHC) nickel complexes will be synthesized to answer the following questions: (i) How do the ligand and the substrate affect cis- versus trans-oxidative addition of carbon-fluorine or sulfur-fluorine bonds at nickel? (ii) Does cis- versus trans-oxidative addition of carbon-fluorine and sulfur-fluorine bonds at nickel affect cross-coupling reactivity for silylation and borylation catalysis? and (iii) How does nickel react with sulfonyl fluorides as compared to aryl fluorides? These studies are expected to provide fundamental information on the structural features that confer maximal reactivity on Ni-NHC complexes for C-F and S-F bond activation.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.