Combining Nickel and Photoredox Catalysis

抽象的。我们研究计划的一个基本目标是开发新型合成材料 战略，将允许有效地构建从 简单，容易获得的起始材料。沿着这些思路，我们的团队致力于 致力于光催化氧化还原在有机合成中的应用。这个催化领域 使用能够吸收可见光的过渡金属络合物或有机染料。 光子的吸收促进光催化剂进入长寿命的激发状态，然后这种状态可能会起作用 通过单电子转移作为氧化剂或还原剂。因此，光氧化还原催化剂利用 可见光作为化学能的来源，可以用来克服重大反应 障碍。最近，我们的团队和其他人证明了光氧化还原催化可以 成功地与其他催化平台合并，以充分利用各自的优势 个性化的催化模式。我们已经变得特别有兴趣探索在 光氧化还原催化与过渡金属交叉偶联催化的界面。在这项研究中 提案中，我们为我们基于光氧化还原多催化的研究计划勾勒出新的方向。 拟议目标的成功完成将使人们能够进入目前未知的或 无法进入的反应路径，并将允许常见的、通常是“无害的”有机化合物 作为交叉偶联反应的参与者而被激活。在AIM I中，我们建议开发一种 光氧化还原和镍催化的不对称脱羧基交叉偶联。在……里面 目的II，我们的目标是利用镍催化剂活化烷基卤化物的能力来实现 SP3-SP3直接交叉偶联。AIM III设想开发一种镍和光氧化还原- 催化二氧化碳挤出将酯转化为高价值支架的方法-- 重组。虽然目标I-III侧重于羧酸的交叉偶联，但目标IV 建议引入一类新的随时可用的耦合伙伴，方法是 简单醇衍生物在镍-光氧化还原交叉偶联中的应用。在目标五中，我们的目标是 使用三种不同的催化剂来完成胺、醚和 醇通过氢原子转移和交叉偶联。Aim VI设想应用一种 相关的三催化策略，以开发一种交叉亲电偶联的方法。在目标七中， 我们的目标是利用光催化控制过渡金属的氧化态，以便 完成镍介导的C-N偶联反应。最后，作为多样性补充的一部分， 目的提出用异丙肾上腺素构筑聚吡咯吲哚生物碱 我们实验室开发的铜催化方法的迭代应用。

Abstract. A fundamental goal of our research program is the development of novel synthetic strategies that will allow for the efficient construction of medicinally useful compounds from simple, readily available starting materials. Along these lines, our group has dedicated significant effort to the application of photoredox catalysis to organic synthesis. This field of catalysis employs transition metal complexes or organic dyes which are capable of absorbing visible light. Absorption of a photon promotes a photocatalyst to a long-lived excited state, which may then act as an oxidant or a reductant via single-electron transfer. As such, photoredox catalysts harness visible light as a source of chemical energy, which can be used to overcome significant reaction barriers. Recently, our group and others have demonstrated that photoredox catalysis can be successfully merged with other catalytic platforms in order to capitalize on the strengths of each individual mode of catalysis. We have become particularly interested in exploring reactivity at the interface of photoredox catalysis and transition metal cross-coupling catalysis. In this research proposal, we outline new directions for our photoredox multicatalysis-based research program. The successful completion of the proposed aims will provide access to currently unknown or inaccessible reaction pathways and will allow common and usually “benign” organic compounds to be activated as participants in cross-coupling reactions. In Aim I, we propose to develop an asymmetric decarboxylative cross-coupling via the merger of photoredox and nickel catalysis. In Aim II, we aim to harness the ability of nickel catalysts to activate alkyl halides to accomplish a direct sp3–sp3 cross-coupling. Aim III envisions the development of a nickel- and photoredox- catalyzed method for the conversion of esters into high-value scaffolds via CO2-extrusion- recombination. While Aims I–III focus on the cross-coupling of carboxylic acids, Aim IV proposes the introduction of a new class of readily available coupling partners by employing simple alcohol derivatives in nickel-photoredox cross-coupling. In Aim V, it is our objective to employ three discrete catalysts in order to accomplish C–H arylation of amines, ethers, and alcohols via hydrogen atom transfer and cross-coupling. Aim VI envisions the application of a related triple-catalytic strategy to develop a method for cross-electrophile coupling. In Aim VII, it is our goal to harness photocatalytic control of transition metal oxidation states in order to accomplish a nickel-mediated C–N coupling reaction. Finally, as part of a Diversity Supplement, Aim VIII proposes the construction of the polypyrroloindoline alkaloid isopsychotridine using iterative applications of a copper-catalyzed method developed in our laboratory.