Institute of Bioorganic & Medicinal Chemistry, Key Laboratory of Luminescence Analysis and Molecular Sensing, Ministry of Education, School of Chemistry and Chemical Engineering, Southwest University, Chongqing, 400715, P. R. China.
Chemistry. 2021 Feb 15;27(10):3278-3283. doi: 10.1002/chem.202004810. Epub 2021 Jan 26.
We report a challenging copper-catalyzed C -H arylation of salicylaldehydes with arylboronic acids that involves unique salicylaldehydic copper species that differ from reported salicylaldehydic rhodacycles and palladacycles. This protocol has high chemoselectivity for the C -H bond compared to the phenolic O-H bond involving copper catalysis under high reaction temperatures. This approach is compatible with a wide range of salicylaldehyde and arylboronic acid substrates, including estrone and carbazole derivatives, which leads to the corresponding arylation products. Mechanistic studies show that the 2-hydroxy group of the salicylaldehyde substrate triggers the formation of salicylaldehydic copper complexes through a Cu /Cu /Cu catalytic cycle.
我们报告了一种具有挑战性的铜催化水杨醛与芳基硼酸的 C-H 芳基化反应，其中涉及到不同于报道的水杨醛铑环和钯环的独特水杨醛铜物种。与涉及铜催化的高温下的酚羟基 O-H 键相比，该反应对 C-H 键具有高化学选择性。该方法与包括雌酮和咔唑衍生物在内的各种水杨醛和芳基硼酸底物兼容，可得到相应的芳基化产物。机理研究表明，水杨醛底物的 2-羟基基团通过 Cu/Cu/Cu 催化循环触发水杨醛铜配合物的形成。
