Ligand-Facilitated Palladium Oxidation Catalysis

描述（由申请人提供）：氧化反应是合成有机化学中最强大的转化之一，因为它们能够增加有机底物的官能度。然而，许多有用的化学计量氧化剂的高成本和毒性促使人们做出大量努力来开发使用容易获得且环境友好的氧化剂的催化转化。配体促进的钯氧化催化是一种新的好氧基质氧化途径。这些反应不需要氧化还原介体如氯化铜（II）或苯醌用于催化转换期间钯（0）的双氧偶联氧化。拟议的研究将检查的范围和效用的配体促进钯氧化催化氧化杂环和碳环化的烯烃底物。这项工作将通过实验室开发的新的并行筛选工具和同时详细的催化反应机理表征来促进。其中的反应要开发的是新的钯催化的分子间氧化氮转移反应，采用分子氧作为化学计量的氧化剂。采用分子氧作为化学计量氧化剂的新型催化氧化在有机化学中具有几乎无限的潜力，特别是对于天然产物和生物活性分子的合成。未来扩展到不对称催化将对药物发现工作产生重大影响。这些反应也是环境友好的，因为它们的副产物是良性的（水）。这些优点，沿着低成本和毒性的分子氧，将使配体促进的钯氧化催化在工业上以及在学术界的合成有机化学家相当有吸引力。

DESCRIPTION (provided by applicant): Oxidation reactions are among the most powerful transformations in synthetic organic chemistry because of their ability to increase the functionality of organic substrates. However, the high costs and toxicity of many useful stoichiometric oxidants have prompted substantial effort to develop catalytic transformations that employ readily available and environmentally benign oxidants. A novel pathway for aerobic substrate oxidation is ligand-facilitated palladium oxidation catalysis. These reactions require no redox mediators such as copper(ll) chloride or benzoquinone for dioxygen-coupled oxidation of palladium(0) during catalytic turnover. The proposed research will examine the scope and utility of ligand-facilitated palladium oxidation catalysis for the oxidative hetero- and carbocyclization of olefinic substrates. This work will be facilitated by new parallel screening tools developed in the lab and simultaneous detailed mechanistic characterization of the catalytic reactions. Among the reactions to be developed are new palladium-catalyzed intermolecular oxidative nitrogen-transfer reactions that employ dioxygen as the stoichiometric oxidant. New catalytic oxidations that employ dioxygen as the stoichiometric oxidant have almost unlimited potential in organic chemistry, particularly for the synthesis of natural products and biologically active molecules. Future expansions into asymmetric catalysis would have a significant impact on drug discovery efforts. These reactions are environmentally friendly as well due to their benign by-products (water). These assets, along with the low cost and toxicity of dioxygen, will make ligand-facilitated palladium oxidation catalysis quite attractive to synthetic organic chemists in industry as well as those in academia.