Catalytic Regioselective Functionalization of Alkane and Arenes

烷烃和芳烃的催化区域选择性官能化

• 批准号: 1213409
• 负责人: John Hartwig
• 金额: $ 52.4万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-06-01 至 2016-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1213409&HistoricalAwards=false
• 关键词: Catalytic; Regioselective; Functionalization; Alkane; Arenes

In this project funded by the Chemical Catalysis Program of the Chemistry Division, Professor John F. Hartwig at the University of California, Berkeley will develop reactions at typically unreactive carbon-hydrogen (C-H) bonds. Prof. Hartwig's group discovered the borylation of methyl C-H bonds in alkanes and alkyl groups of functionalized molecules and developed iridium complexes that catalyze the borylation of aryl and alkyl C-H bonds under mild conditions, with sterically controlled selectivity, including reactions that occur with high turnovers. The proposed research builds upon several sets of preliminary data on the silylation of C-H bonds, the borylation of aliphatic C-H bonds with a new iridium catalyst, and the factors that control selectivity in these C-H bond functionalizations. The proposed research will broaden the scope of the borylations of alkyl C-H bonds to include the borylation of secondary C-H bonds and activated primary C-H bonds, directed borylations by strategies related to this group's recently discovered directed silylations of alkyl C-H bonds, and aspects of intermolecular C-H bond silylations of arenes, heteroarenes, and alkenes. The proposed research will also gain insight into the mechanism of silylations and borylations of C-H bonds by preparing boryl and silyl complexes that are competent to be intermediates in the recently discovered borylations of aliphatic C-H bonds and silylations of aliphatic and aromatic C-H bonds.For many years, chemical synthesis has focused on reactions at particular points of a molecule that contains a reactive array of atoms called "functional groups." The C-H bonds distal from these functional groups are usually unreactive with reagents used for conventional synthetic chemistry. The proposed research focuses on reactions that occur selectively at the C-H bonds of a molecule that are typically unreactive. One challenge that must be met to achieve this goal is the selective functionalization of a specific C-H bond in a molecule. In some cases, the selectivity for one C-H bond results from the spatial availability of the bond, in some cases from the distribution of electrons around the bond, and in other cases from the position of a functional group several atoms away from the C-H bond. Methods to exploit each of these properties for selectivity will be uncovered. This research will lead to new methods to conduct chemical synthesis in fewer steps, with less waste, and with less reliance on the installation and protection of functional groups. In addition, this research creates the underlying principles on which future design of catalysts and processes for more efficient synthesis are based. This may impact the synthesis of useful materials such as polymers containing new properties, organic molecules with enhanced abilities to emit light, components of catalysts for other reactions, organic probes for understanding biological systems, and components of medicinally important molecules. Work emanating from the proposed research has become part of new curricula for the classroom, short-courses, many external lectures, and a major textbook project that was recently completed by the PI.

在这个由化学系化学催化计划资助的项目中，约翰·F·加州大学伯克利分校的Hartwig将在典型的不活泼的碳氢（C-H）键上进行反应。Hartwig教授的研究小组发现了官能化分子的烷烃和烷基中甲基C-H键的硼基化，并开发了铱络合物，该络合物在温和条件下催化芳基和烷基C-H键的硼基化，具有空间控制的选择性，包括发生高周转率的反应。拟议的研究建立在C-H键的甲硅烷基化，脂肪族C-H键与新的铱催化剂的硼基化，以及控制这些C-H键官能化的选择性的因素的几组初步数据。拟议的研究将扩大范围的烷基C-H键的硼基化，包括仲C-H键和活化的伯C-H键的硼基化，定向硼基化的策略相关的该组最近发现的烷基C-H键的定向硅烷化，和芳烃，杂芳烃和烯烃的分子间C-H键硅烷化的方面。所提出的研究还将通过制备硼基和甲硅烷基络合物来深入了解C-H键的甲硅烷基化和硼基化的机理，所述硼基和甲硅烷基络合物有能力成为最近发现的脂肪族C-H键的硼基化和脂肪族和芳香族C-H键的甲硅烷基化的中间体。化学合成集中在包含称为“官能团”的原子反应阵列的分子的特定点处的反应。“远离这些官能团的C-H键通常与用于常规合成化学的试剂不反应。拟议的研究重点是选择性地发生在通常不反应的分子的C-H键上的反应。要实现这一目标必须满足的一个挑战是分子中特定C-H键的选择性官能化。在某些情况下，对一个C-H键的选择性由键的空间可用性产生，在某些情况下由键周围的电子分布产生，并且在其他情况下由远离C-H键几个原子的官能团的位置产生。将揭示利用这些特性中的每一个进行选择性的方法。这项研究将导致新的方法，以更少的步骤进行化学合成，减少浪费，减少对功能基团的安装和保护的依赖。此外，这项研究创造了未来设计催化剂和更有效合成工艺的基本原则。这可能会影响有用材料的合成，例如含有新特性的聚合物，具有增强发光能力的有机分子，用于其他反应的催化剂组分，用于理解生物系统的有机探针以及医学重要分子的组分。从拟议的研究产生的工作已成为新的课程的一部分，为课堂，短期课程，许多外部讲座，以及一个主要的教科书项目，是最近完成的PI。