Transition Metal Complexes with Chiral Pincer Ligands: Reactions, Catalyses, Mechanisms

本研究计画系关于手性钳形配体作为立体定向配体在不对称选择性催化中之配位化学。一个主要的目标将是评估在何种程度上这类配体可以在不同范围的对映体选择性转化的ALS“特权”立体定向配体系统。计划研究的一个目的将是分离和表征的（高自旋）的briddo和boranato-衍生物的Boxmi-锰，铁，钴和镍配合物的对映选择性催化还原与这些3D金属的关键中间体，以及使用分离的配合物的化学计量和催化还原的系统动力学研究。此外，我们的目标是开发有效的氧化催化剂的基础上，最近发现的Ni（I/II）催化的radikal氧化与O2作为共底物，这些转变的正在进行的机理研究将继续进行，并追求更深入。最后，我们计划研究Boxmi锰配合物作为酮的对映选择性α-酰氧基化的可能催化剂，反应机理，并确定所涉及的（电子开壳，顺磁性）配合物。

The research project concerns the coordination chemistry of such chiral pincer ligands as stereodirecting ligands in enantioselective catalysis. A main objective will be to assess to which extent this class of ligands may serve als "privileged" stereodirecting ligand systems in a diverse range of enantioselective transformations. An aim of the planned research will be the isolation and characterization of (high spin) hydrido and boranato-derivatives of Boxmi-manganese, iron, cobalt and nickel complexes as key intermediates of enantioselective catalytic reductions with these 3d metals as well as the use of the isolated complexes in systematic kinetic studies of the stoichiometric and catalytic reductions. Furthermore, we aim to develop efficient oxidation catalysts based on the recently discovered Ni(I/II) catalyzed radikal oxygenations with O2 as co-substrate, and ongoing mechanistic studies of these transformations will be continued and pursued to greater depth. Finally we plan to investigate Boxmi-manganese complexes as possible catalysts for the enantioselective alpha-acyloxylation of ketones, the reaction mechanism(s) and identify the (electronically open shell, paramagnetic) complexes involved.