The oxidativebromination of arenes was induced by a vanadium catalyst in the presence of a bromide salt and a Brønsted acid or a Lewis acid under molecular oxygen, which provides an eco-friendly bromination method as compared with a conventional bromination one with bromine. This catalytic reaction could be applied to the bromination of alkenes and alkynes to give the corresponding vic-bromides. Use
芳烃的氧化溴化反应是在分子氧下,在溴化物盐和布朗斯台德酸或路易斯酸存在下,由钒催化剂诱导的,与传统的溴化溴化方法相比,该方法提供了一种环保的溴化方法。这种催化反应可以适用于烯烃和炔烃的溴化,得到相应的VIC -溴化物。已证明使用卤化铝代替布朗斯台德酸作为路易斯酸可为氧化溴化提供更实用的方法。从酮中获得α-溴化产物。发现AlBr 3既是溴化物源又是路易斯酸,可以顺利地诱导溴化。511 H NMR实验表明,这种催化溴化反应可能取决于分子氧下钒催化剂的氧化还原循环。
Oxidative bromination reaction using vanadium catalyst and aluminum halide under molecular oxygen
The vanadium-catalyzed oxidative brominationreaction of arenes, alkenes, and alkynes was performed in the presence of AlBr3 to provide an alternative method for conventional bromination using hazardous bromine. The catalytic cycle is formed under molecular oxygen, which is more advantageous to vanadiumbromoperoxidase (VBrPO) requiring hydrogen peroxide as a terminal oxidant.
Metal-free oxidative brominationreactions in aqueous media were performed using tetrabutylammonium bromide, trifluoroacetic acid, and hydrogen peroxide under mild conditions. Oxidative brominationreaction of alkenes was found to afford the corresponding vic-bromides. Furthermore, this oxidative brominationsystem is applicable to the oxidative bromination of alkynes, arenes, and 3,4-dihydronaphthalen-1(2H)-one