Department of Chemistry and Biochemistry, Graduate School of Engineering, Kyushu University 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan.
Institute for Materials Chemistry and Engineering, Kyushu University 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan.
Dalton Trans. 2020 Jun 9;49(22):7546-7551. doi: 10.1039/d0dt01377c.
Imine/Oxime-type cobalt complexes, regarded as simple vitamin B12 model complexes, were utilized as catalysts for direct C-H perfluoroalkylations of indole and aniline derivatives with nonafluorobutyl iodide (n-C4F9I) as the readily available perfluoroalkyl source. The synthetic approach described herein was performed under mild reaction conditions driven by controlled-potential electrolysis at -0.8 V vs. Ag/AgCl in organic solvents. The mechanistic investigations suggest that a nonafluorobutyl radical is mediated by homolytic cleavage of the cobalt(iii)-carbon bond in the catalytic cycle. This is the first report concerning a fluoroalkylation reaction of (hetero)aromatics catalyzed by the simple vitamin B12 model complex. The convenient electrocatalytic method employing a simple cobalt complex provides a facile synthesis method toward novel fluoroalkylated compounds, demonstrating potential applications in the fields of pharmaceutical chemistry and materials science.
亚胺/肟型钴配合物被视为简单的维生素 B12 模型配合物，可用作吲哚和苯胺衍生物与全氟丁基碘化物（n-C4F9I）直接 C-H 全氟烷基化反应的催化剂，全氟丁基碘化物是易得的全氟烷基源。本文所描述的合成方法是在温和的反应条件下，通过在有机溶剂中-0.8 V 对 Ag/AgCl 进行恒电位电解来进行的。机理研究表明，在催化循环中，通过钴（III）-碳键的均裂来介导全氟丁基自由基。这是首例由简单的维生素 B12 模型配合物催化的（杂）芳族化合物的氟烷基化反应的报道。该方法采用简单的钴配合物作为电催化剂，提供了一种方便的合成新型全氟烷基化合物的方法，在药物化学和材料科学领域具有潜在的应用价值。
