Control of reactive site in palladium-catalyzed Grignard cross-coupling of arenes containing both bromide and triflate
Control of reactive site in palladium-catalyzed Grignard cross-coupling of arenes containing both bromide and triflate
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DOI：
10.1016/s0040-4039(97)01655-9
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发表时间：
1997-10-06
影响因子：
1.8
通讯作者：
Hayashi, T
中科院分区：
文献类型：
--
作者：
Kamikawa, T;Hayashi, T
对溴苯基三氟甲磺酸酯（1）与苯基溴化镁在5mol%PdCl_2（dppp）存在下反应，生成4-溴联苯（2a），收率97%。另一方面，用PdCl_2（meo-mop）（2）选择性地将1中的溴代物与苯基格氏试剂取代，高产率地得到4-联苯三氟甲磺酸酯（3a）。在1与钯（0）膦络合物的化学计量反应中，选择性取代被证明发生在钯（0）物种的氧化加成步骤中。(C)1997 Elsevier Science Ltd.
Reaction of 4-bromophenyl triflate (1) with phenylmagnesium bromide in the presence of 5 mol % of PdCl2(dppp) gave 97% yield of 4-bromobiphenyl (2a), which was formed by selective replacement of triflate in 1 by phenyl. On the other hand, bromide in 1 was substituted with the phenyl Grignard reagent selectively by use of PdCl2(meo-mop)(2) to give 4-biphenyl triflate (3a) in high yield. The selective substitution was demonstrated to take place at the oxidative addition step to a palladium(0) species in a stoichiometric reaction of 1 with palladium(0) phosphine complexes. (C) 1997 Elsevier Science Ltd.