• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Chemistry: A European journal >A General Palladium-Catalyzed Amination of Aryl Halides with Ammonia
【24h】

A General Palladium-Catalyzed Amination of Aryl Halides with Ammonia

机译：普通钯催化的氨化卤代甲烷氨化

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

Anilines are important intermediates in the manufacture of agrochemicals, dyes, pharmaceuticals, and other industrial products.[1] Hence, there is a continuing interest in easier and more cost-efficient preparations.[2] In the past decade transition-metal-catalyzed CSTXN bond-forming reactions have emerged as a potent tool for the production of aryl amines. Due to the seminal contributions of the groups of Buchwald and Hartwig, palladium-catalyzed CSTXN cross-coupling reactions of aryl halides with various N-nucleophiles have become one of the most valuable organic transformations.[ 3] Despite the impressive results in the production of secondary and tertiary amines,[4] relatively little work has been done on the amination of aryl halides to produce primary aryl amines. Problems encountered with the direct utilization of ammonia are: 1) the displacement of the ligand bound to the Pd center by ammonia leading to a catalytically non-reactive complex,[5] 2) the tendency of complexes bearing an amido group to form stable bridging structures,[6] and 3) the increased activity of a resulting primary aniline compared to ammonia leading to diaryl amines. To avoid these problems synthetic equivalents of ammonia have been employed including allyl,[7] benzyl,[8] and silyl amines,[9] imines,[10] and amides.[11] Unfortunately, the corresponding coupling products have to be cleaved after the reaction, which leads to unwanted side products.[12] Hence, the use of ammonia as an N-nucleophile is still by far the most desired approach[13] because of its inherent atom economy, and the low cost and availability of ammonia.
机译：苯胺是制造农业化学品，染料，药物和其他工业产品的重要中间体。[1]因此，人们对更简便，更具成本效益的准备工作产生了持续的兴趣。[2]在过去的十年中，过渡金属催化的CSTXN键形成反应已经成为生产芳基胺的有效手段。由于布赫瓦尔德（Buchwald）和哈特维希（Hartwig）基团的开创性贡献，芳基卤化物与各种N-亲核试剂的钯催化CSTXN交叉偶联反应已成为最有价值的有机转化之一。[3]仲和叔胺，[4]在芳基卤化物的胺化过程中，生产伯芳基胺的工作相对较少。直接利用氨所遇到的问题是：1）氨将结合到Pd中心的配体置换，导致催化非反应性络合物，[5] 2）带有酰胺基的络合物趋于形成稳定的桥连结构[6]和3），与氨相比，生成的伯苯胺的活性增加，从而导致二芳基胺的生成。为避免这些问题，已使用了氨当量的合成当量，包括烯丙基，[7]苄基，[8]和甲硅烷基胺，[9]亚胺，[10]和酰胺。不幸的是，反应后必须裂解相应的偶联产物，这会导致产生不需要的副产物。[12]因此，由于其固有的原子经济性以及氨的低成本和可用性，使用氨作为N-亲核试剂仍然是迄今为止最需要的方法。

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