Wöhler Research Institute for Sustainable Chemistry, Georg-August-Universität Göttingen, 37077 Göttingen, Germany.
Science. 2023 Mar 10;379(6636):1036-1042. doi: 10.1126/science.adg2866. Epub 2023 Mar 9.
Enantioselective redox transformations typically rely on costly transition metals as catalysts and often stoichiometric amounts of chemical redox agents as well. Electrocatalysis represents a more sustainable alternative, in particular through the use of the hydrogen evolution reaction (HER) in place of a chemical oxidant. In this work, we describe strategies for HER-coupled enantioselective aryl carbon-hydrogen bond (C-H) activation reactions using cobalt in place of a precious metal catalyst for the asymmetric oxidation. Thus, highly enantioselective carbon-hydrogen and nitrogen-hydrogen (C-H and N-H) annulations of carboxylic amides were achieved, which gave access to point and axially chiral compounds. Furthermore, the cobalt-mediated electrocatalysis enabled the preparation of various phosphorus (P)-stereogenic compounds by selective desymmetrization through dehydrogenative C-H activation reactions.
对映选择性氧化还原转化通常依赖于昂贵的过渡金属作为催化剂，并且通常还需要化学氧化还原试剂的化学计量。电催化是一种更可持续的替代方法，特别是通过使用析氢反应 (HER) 代替化学氧化剂。在这项工作中，我们描述了使用钴代替贵金属催化剂用于不对称氧化的 HER 偶联对映选择性芳基碳-氢键 (C-H) 活化反应的策略。因此，实现了高度对映选择性的碳-氢键和氮-氢键 (C-H 和 N-H) 环化反应，得到了点手性和轴向手性化合物。此外，钴介导的电催化通过脱氢 C-H 活化反应的选择性去对称化，能够制备各种磷 (P)-手性化合物。
