Kaiser oxime resin-derived palladacycle: A recoverable polymeric precatalyst in Suzuki-Miyaura reactions in aqueous media
Kaiser oxime resin-derived palladacycle: A recoverable polymeric precatalyst in Suzuki-Miyaura reactions in aqueous media
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DOI：
10.1016/j.jorganchem.2009.01.016
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发表时间：
2009-05-01
影响因子：
2.3
通讯作者：
Najera, Carmen
中科院分区：
文献类型：
--
作者：
Alacid, Emilio;Najera, Carmen
以凯泽肟树脂为预催化剂，碳酸钾为碱，以聚合物键合的钯环为预催化剂，在水回流条件下进行了芳基溴与不同类型芳基、烷基、三乙烯基硼氧吡啶配合物和烯基硼酸的代表性交叉偶联反应。这些工艺分别产生联苯、烷基苯、苯乙烯和二苯乙烯。同样的硼酸可以与代表性的烯丙基氯和苯氯交叉偶联，以KOH为碱，在50℃的丙酮水溶液中产生烯丙基苯、二甲基甲烷和1,4-戊二烯。钯化聚合物可以通过过滤回收，并在3-9个循环中重复使用，每次运行的Pd浸出率高达5%。通过ICP-OES分析可以确定原油中极低的Pd浸出水平。当加入Hg(0)时，反应不发生。TEM分析表明，溶液中形成了钯纳米粒子。(C) 2009 Elsevier B.V.版权所有
Representative cross-coupling reactions of aryl bromides with different types of aryl-, alkyl, trivinylboroxine-pyridine complex, and alkenylboronic acids are performed using a polymer-bonded palladacycle derived from Kaiser oxime resin as precatalyst and potassium carbonate as base under water reflux. These processes afford biphenyls, alkylbenzenes, styrenes, and stilbenes, respectively. The same boronic acids can be cross-coupled with representative allyl and benzyl chlorides using KOH as base in aqueous acetone at 50 degrees C providing allylbenzenes, diarylmethanes, and 1,4-pentadienes. The palladated polymer can be recovered by filtration and reused during 3-9 cycles with up to 5% of Pd leaching in each run. Very low Pd leaching levels in the crude product can be determined by ICP-OES analyses. The reaction does not work when Hg(0) is added. TEM analyses from the solution indicate the formation of Pd nanoparticles. (C) 2009 Elsevier B.V. All rights reserved.