Copper-Catalyzed Electrochemical Selective B-H Oxygenation of o-Carboranes at Room Temperature
Copper-Catalyzed Electrochemical Selective B-H Oxygenation of o-Carboranes at Room Temperature
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DOI：
10.1021/jacs.0c02490
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发表时间：
2020-04-15
影响因子：
15
通讯作者：
Xie, Zuowei
中科院分区：
文献类型：
--
作者：
Au, Yik Ki;Lyu, Hairong;Xie, Zuowei
首次实现了铜催化的邻碳硼烷笼式B-H氧化反应。在室温下，在恒定电流（4.0 mA）下，铜催化的碳硼烷酰胺与苯酚锂的交叉偶联导致通过直接B-H活化形成B（4，5）-二苯酚化的o-碳硼烷，而使用叔丁醇锂提供B（4）-单氧化产物。该反应不需要任何额外的化学氧化剂，并产生H2和锂盐作为副产物。对照实验表明，高价Cu（III）物种可能参与反应过程。
Copper-catalyzed electrochemical selective cage B-H oxygenation of o-carboranes has been achieved for the first time. Under a constant electric current (4.0 mA) at room temperature, copper-catalyzed cross-coupling of carboranyl amides with lithium phenolates results in the formation of B(4,5)-diphenolated o-carboranes via direct B-H activation, whereas the use of lithium tert-butoxide affords B(4)-monooxygenated products. This reaction does not require any additional chemical oxidants and generates H-2 and a lithium salt as byproducts. Control experiments indicated that a high-valent Cu(III) species is likely involved in the reaction process.