• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Chemistry: A European journal >In Situ Generation of ArCu from CuF2 Makes Coupling of Bulky Aryl Silanes Feasible and Highly Efficient
【24h】

In Situ Generation of ArCu from CuF2 Makes Coupling of Bulky Aryl Silanes Feasible and Highly Efficient

机译：从CuF2原位生成ArCu使大体积芳基硅烷的偶联可行且高效

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

A bimetallic system of Pd/CuF2, catalytic in Pd and stoichiometric in Cu, is very efficient and selective for the coupling of fairly hindered aryl silanes with aryl, anisyl, phenylaldehyde, p-cyanophenyl, p-nitrophenyl, or pyridyl iodides of conventional size. The reaction involves the activation of the silane by Cu-II, followed by disproportionation and transmetalation from the Cu-I(aryl) to Pd-II, upon which coupling takes place. Cu-III formed during disproportionation is reduced to Cu-I(aryl) by excess aryl silane, so that the CuF2 system is fully converted into Cu-I(aryl) and used in the coupling. Moreover, no extra source of fluoride is needed. Interesting size selectivity towards coupling is found in competitive reactions of hindered aryl silanes. Easily accessible [PdCl2(IDM)(AsPh3)] (IDM = 1,3-dimethylimidazol-2-ylidene) is by far the best catalyst, and the isolated products are essentially free from As or Pd (<1ppm). The mechanistic aspects of the process have been experimentally examined and discussed.
机译：Pd / CuF2的双金属体系（在Pd中催化并在Cu中以化学计量）非常有效且具有选择性，可将相当受阻的芳基硅烷与常规尺寸的芳基，茴香基，苯甲醛，对氰基苯基，对硝基苯基或吡啶基碘化物偶联。该反应涉及通过Cu-II活化硅烷，然后歧化和从Cu-I（芳基）到Pd-II的重金属转移，然后发生偶联。在歧化过程中形成的Cu-III被过量的芳基硅烷还原为Cu-I（芳基），因此CuF2系统被完全转化为Cu-I（芳基）并用于偶联。而且，不需要额外的氟化物源。在受阻芳基硅烷的竞争反应中发现了对偶联的有趣的尺寸选择性。到目前为止，易于获得的[PdCl2（IDM）（AsPh3）]（IDM = 1,3-二甲基咪唑-2-亚基）是最好的催化剂，分离出的产物基本上不含As或Pd（<1ppm）。该过程的机械方面已通过实验检查和讨论。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号