• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>RSC Advances >Mechanism of the gold(I)-catalyzed synthesis of imidazo-pyrimidines and imidazo-pyrazines via [3+2] dipolar cycloaddition: a DFT study
【24h】

Mechanism of the gold(I)-catalyzed synthesis of imidazo-pyrimidines and imidazo-pyrazines via [3+2] dipolar cycloaddition: a DFT study

机译：黄金（I）的机制 - 通过[3 + 2] DIPOLAR环加成（DFT研究） - 催化咪唑 - 嘧啶和咪唑吡嗪和咪唑吡嗪合成：DFT研究

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

Density functional theory calculations have been carried out to study the mechanisms of gold(I)-catalyzed [3 + 2] cycloaddition reactions of pyridinium N-(heteroaryl)-aminides, as nucleophilic nitrenoids, with electron-rich alkynes, leading to imidazo-pyrimidines and imidazo-pyrazines. The calculation results suggest that the reaction mainly involves two plausible pathways leading to different products, since two carbon atoms of the asymmetric alkyne are attacked selectively by the aminide nitrogen atom. These reaction steps include C-C bond activation of the alkyne by the gold complex, a bimolecular nucleophilic attack, a closed-loop process and migration of the pyridine molecule to finally give cycloaddition products. The closed-loop process is the rate-limiting step for the whole catalytic reaction and the energy barrier shows that the pathway of the nucleophile onto the amide carbon atom of the alkyne with the electron-withdrawing group is favored. Through a detailed mechanistic investigation, we have explained the regioselectivity and the major/minor products observed by Davies et al. in gold(I)catalyzed [3 + 2] cycloaddition reactions of nucleophilic nitrenoids with electron-rich alkynes.
机译：已经进行了密度函数理论计算，以研究吡啶鎓N-（杂芳基）-MiniNate的黄金（I）的机制 - 催化[3 + 2] - 氨基吡啶胺，作为亲核硝基苯，导致Imidazo-嘧啶和咪唑吡嗪。计算结果表明，该反应主要涉及两种通向不同产品的合理途径，因为不对称炔烃的两个碳原子由氨基氮原子选择性地受到攻击。这些反应步骤包括黄金复合物的C-C键活化，双分子亲核攻击，闭环过程和吡啶分子的迁移最终给予环加成产品。闭环过程是整个催化反应的速率限制步骤，并且能量屏障表明，亲核官到炔烃与电子取出基团的酰胺碳原子的途径有利。通过详细的机制调查，我们解释了Davies等人观察到的区域选择性和主要/次要产品。在金（I）中催化亲核硝基苯的循环加油反应与电子富含电子炔烃。

著录项

  • 来源
    《RSC Advances》 |2016年第67期|共10页
  • 作者

    Zhang Xinghui; Geng Zhiyuan;

  • 作者单位

    Lanzhou Univ Arts &

    Sci Coll Chem Engn Lanzhou 730010 Gansu Peoples R China;

    Northwest Normal Univ Gansu Key Lab Polymer Mat Coll Chem &

    Chem Engn Key Lab Ecoenvironm Related Polymer Mat Minist Ed Lanzhou 730070 Gansu Peoples R China;

  • 收录信息
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类 化学;
  • 关键词

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