化学学报 ›› 2011, Vol. 69 ›› Issue (23): 2851-2858.DOI: 10.6023/A1103229 上一篇    下一篇

研究论文

K3PO4-催化的β-硝基苯乙烯衍生物与乙酰胺、NBS的区域专一性氨溴加成反应研究

陈战国, 周继梅, 王芸, 李文丽   

  1. (陕西省大分子科学重点实验室   陕西师范大学化学化工学院  西安710062)
  • 投稿日期:2011-03-22 修回日期:2011-06-23 发布日期:2011-08-16
  • 通讯作者: 陈战国 E-mail:chzhg@snnu.edu.cn
  • 基金资助:

    烯键上的区域选择和立体选择性氨卤加成反应研究;碳碳双键上的不对称氨卤加成反应研究

K3PO4-Catalyzed Regiospecific Aminobromination of β-Nitrostyrene Derivatives with acetamide and NBS

CHEN Zhan-Guo, ZHOU Ji-Mei, WANG Yun, LI Wen-Li   

  • Received:2011-03-22 Revised:2011-06-23 Published:2011-08-16
  • Contact: Chen Zhan-guo E-mail:chzhg@snnu.edu.cn

摘要 在无水磷酸钾催化下,以乙酰胺(CH3CONH2)和N-溴代丁二酰亚胺(NBS)为氮源和卤素源,丙酮作溶剂,建立了β-硝基苯乙烯双键上的区域专一性氨溴加成反应新体系。该法在室温下,无需惰性气体保护可高收率的获得邻位氨卤加成产物,最高收率可达79 % 。实验证明,当β-硝基苯乙烯中苯环4-位具有强供电子基团时(如CH3O),该反应的活性较低,同时得到唯一的α-氨基-β-二溴加成产物;当β-硝基苯乙烯中苯环4-位有强吸电子基团(如NO2)时,该反应的活性较高,同时也得到唯一的α-氨基-β-二溴加成产物。这一实验结果证明了β-硝基苯乙烯衍生物(缺电子烯键)在该条件下的氨溴加成反应是一个亲核加成反应。本文共考察了14种不同结构的β-硝基苯乙烯的氨溴加成反应情况,其产物结构经核磁共振氢谱、碳谱、及元素分析确证,并提出了可能的反应机理。

A regiospecific method for the aminobromination of β-nitrostyrene derivatives with acetamide and NBS as aminobrominating agent catalyzed by K3PO4 has been developed in acetone. The method can conveniently and efficiently convert β-nitrostyrenes into vicinal haloamines at room temperature in good yields up to 79 % and without the protection of an inert gaseous atmosphere. Strong electron-donating substituents(e.g.,OCH3) on the 4-position of benzene ring deactivated the reaction activity of β-nitrostyrenes and afforded a sole vicinal haloamine compound. Whereas strong electron-withdrawing substituents(e.g., NO2) activated reaction activity of them remarkably and afforded a sole vicinal haloamine compound, too. The result revealed that the addition reaction has an nucleophilic addition feature. The aminobromination of 14 examples of β-nitrostyrenes have been investigated in this work and the structure of all products were confirmed by their corresponding 1H NMR, 13C NMR spectra and their elemental analysis. A possible mechanism involving a nucleophilic conjugate addition was proposed.