Reactivity of alkali and alkaline earth metal tetrafluorobromates towards aromatic compounds and pyridine
作者:Vasily I. Sobolev、Victor D. Filimonov、Roman V. Ostvald、Vyacheslav B. Radchenko、Ivan I. Zherin
DOI:10.1016/j.jfluchem.2016.10.022
日期:2016.12
The bromination activity of tetrafluorobromates of alkali and alkali-earth metals increases in the order KBrF4, CsBrF4, RbBrF4 and Ba(BrF4)2. The most active tetrafluorobromate—Ba(BrF4)2 is able to selectively brominate the deactivated aromatic compounds nitrobenzene and 4-nitrotoluene, but not the activated compounds benzene and toluene. In all cases bromination of methyl groups of methylbenzenes
碱金属和碱土金属四氟溴酸盐的溴化活性按KBrF 4,CsBrF 4,RbBrF 4和Ba(BrF 4)2的顺序增加。活性最高的四氟溴酸盐-Ba(BrF 4)2能够选择性地溴化失活的芳族化合物硝基苯和4-硝基甲苯,但不能选择性地溴化活化的苯和甲苯。在所有情况下,都不发生甲基苯的甲基溴化。Ba(BrF 4)2与吡啶反应形成已知的络合物C 6 H 5 N·BrF 3。由于用惰性BaF 2稀释,这种基于吡啶的配合物是空气稳定的,与原始的氟代溴酸盐相比,可以认为是更安全,更方便的试剂;与四氟溴酸盐相比,它可以选择性地溴化苯和甲苯。