化学学报 ›› 2011, Vol. 69 ›› Issue (9): 1065-1069. 上一篇    下一篇

研究论文

5-氯-2-硝基苯胺合成5-氯-苯并氧化呋咱反应的密度泛函研究

侯春园1,陈晓芳1,2,刘建勇*,1,王伯周2   

  1. (1中国科学院大连化学物理研究所 分子反应动力学国家重点实验室 大连 116023)
    (2西安近代化学研究所 西安 710065)
  • 投稿日期:2010-07-15 修回日期:2010-11-01 发布日期:2011-01-03
  • 通讯作者: 刘建勇 E-mail:jianyongliu01@163.com

A Density Functional Theory Study of the Synthesis of 5-Chloro-benzofuroxan from 5-Chloro-2-nitroaniline

Hou Chunyuan1 Chen Xiaofang1,2 Liu Jianyong*,1 Wang Bozhou2   

  1. (1 Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023)
    (2 Xi an Modern Chemistry Research Institute, Xi an 710065)
  • Received:2010-07-15 Revised:2010-11-01 Published:2011-01-03
  • Contact: Jianyong Liu E-mail:jianyongliu01@163.com

利用密度泛函理论(DFT)的B3LYP/6-31G(d,p)计算方法研究了次氯酸钠氧化环化5-氯-2-硝基苯胺合成5-氯-苯并氧化呋咱的反应, 采用连续介质模型(PCM)评估了溶剂效应. 提出两种可能的分步反应通道: (1)氧化、移氢、脱水和环化, (2)移氢、亚氨基氢扭转、氧化、脱水和环化|前者为优势通道. 非极性的CCl4溶剂有较低的活化能垒, 比极性的乙醇溶剂更有利于5-氯-2-硝基苯胺的合成. 标题反应的机理类似于次氯酸钠氧化邻硝基苯胺合成苯并氧化呋咱, 但其速控步的活化能垒更低, 反应更易进行.

关键词: 苯并氧化呋咱, 呋咱, 5-氯-2-硝基苯胺, 次氯酸钠, 密度泛函

The oxidative cyclization reaction of 5-chloro-2-nitroaniline via sodium hypochlorite to yield 5-chloro-benzofuroxan is investigated by the hybrid density functional theory (DFT) B3LYP/6-31G(d,p) method. Solvent effects are estimated with the polarizable continuum model (PCM) model to optimize structures. Two possible stepwise pathways are proposed: (1) oxidization, hydrogen transfer, dehydration and cyclization, (2) hydrogen transfer, hydrogen rotation in imine, oxidation, dehydration, and cyclization|the former is a favored process with the lower activation barrier. Our results show that the reaction in very nonpolar solutions such as CCl4 has a lower activation barrier than for polar solutions such as ethanol. Compared with the reaction of 2-nitroaniline via sodium hypochlorite, title reaction with the similar mechanism is more favored because of the lower activation barrier at the rate-determining step (RDS).

Key words: benzofuroxan, furaxan, 5-chloride-2-nitroaniline, sodium hypochlorite