Studies on the Use of Cationic Iridium(III) Complexes in Lewis Acid-Catalyzed C-C Bond-Forming Reactions

在本项目中，将研究阳离子八面体铱（III） d6配合物在主要涉及纳扎罗夫环化的反应中对C-C键形成的催化行为。将研究具有相邻不稳定结合位点的阳离子Ir（III）配合物催化Nazarov环化的动力学和机制，包括详细检查底物结合以及靶向底物变化，以探测Lewis酸度和配体修饰，以评估催化剂有效性的电子和空间效应。Ir（III）配合物将被用作串联或级联反应序列的催化剂，由纳扎罗夫环化引发，在单锅程序中产生具有多个立体中心的复杂碳环体系。具有不稳定邻位的手性Ir（III）催化剂将被开发用于不对称Nazarov环化和串联反应。有了这个奖项，有机和大分子化学项目支持了罗切斯特大学化学系的理查德·艾森伯格博士和艾莉森·j·弗瑞斯特博士的研究。在构建复杂有机分子（包括天然产物和药物活性化合物）的合成方法的发展中，催化仍然处于最前沿。该项目代表了无机化学家和有机化学家之间的新合作，无机化学家的主要研究重点是利用铂族元素进行键激活和催化，有机化学家的研究项目从有机金属化合物的合成方法开发扩展到天然产物的全合成。Drs。Eisenberg和Frontier将探索特定铱催化反应进行的基本机制，并利用所得到的信息开发出更高度控制的反应。这些研究又将有助于发展适用于商品和精细化学品合成的新合成方法。

In this project, the catalytic behavior of cationic octahedral iridium(III) d6 complexes will be studied for C-C bond formation in reactions principally involving the Nazarov cyclization. The kinetics and mechanism of Nazarov cyclization catalyzed by cationic Ir(III) complexes having adjacent labile binding sites will be studied, including a detailed examination of substrate binding coupled with targeted substrate variation to probe Lewis acidity and ligand modification to assess electronic and steric effects on catalyst effectiveness. The Ir(III) complexes will be exploited as catalysts for tandem or cascade reaction sequences initiated with Nazarov cyclization to create complex carbocyclic systems with multiple stereocenters in single pot procedures. Chiral Ir(III) catalysts with labile adjacent sites will be developed for both asymmetric Nazarov cyclization and tandem reactions.With this award, the Organic and Macromolecular Chemistry Program is supporting the research of Dr. Richard Eisenberg and Dr. Alison J. Frontier, of the Department of Chemistry at the University of Rochester. In the development of synthetic methods for the construction of complex organic molecules including natural products and pharmaceutically active compounds, catalysis remains at the forefront. This project represents a new collaboration between an inorganic chemist whose main research focus has been on bond activation and catalysis using platinum group elements and an organic chemist whose research program extends from synthetic methodology development using organometallic compounds to the total synthesis of natural products. Drs. Eisenberg and Frontier will explore the fundamental mechanisms by which particular iridium-catalyzed reactions proceed, with the resulting information allowing them to develop more highly controlled reactions. These studies will in turn permit the development of new synthetic methodologies applicable to the synthesis of commodity and fine chemicals.