物理化学学报 >> 2016, Vol. 32 >> Issue (2): 422-428.doi: 10.3866/PKU.WHXB201512082

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2, 6-二甲氧基-2-嘧啶氧基-N-芳基苄胺衍生物的酸催化Smiles重排反应动力学

张培志1,2,*(),叶美君3,胡伟莲1,吴军4,*()   

  1. 1 浙江科技学院生物与化学工程学院, 杭州 310023
    2 浙江科技学院,浙江省废弃物生物质循环利用与生态处理技术重点实验室, 杭州 310023
    3 中华全国供销合作总社杭州茶叶研究院, 杭州 310016
    4 浙江大学化学系, 杭州 310027
  • 收稿日期:2015-08-24 发布日期:2016-01-30
  • 通讯作者: 张培志,吴军 E-mail:zhangpz@zust.edu.cn;wujunwu@zju.edu.cn
  • 基金资助:
    国家自然科学基金(31471807);公益性行业(农业)科研专项(201403030)

Kinetics of Acid-Catalyzed Smiles Rearrangement of 2, 6-Dimethoxy-2-pyrimidinyloxy-N-arylbenzylamine Derivatives

Pei-Zhi ZHANG1,2,*(),Mei-Jun YE3,Wei-Lian HU1,Jun WU4,*()   

  1. 1 School of Biological and Chemical Engineering, Zhejiang University of Science and Technology, Hangzhou 310023, P. R. China
    2 Key Laboratory of Recycling and Eco-treatment of Waste Biomass of Zhejiang Province, Zhejiang University of Science and Technology, Hangzhou 310023, P. R. China
    3 Hangzhou Tea Research Institute, China COOP, Hangzhou 310016, P. R. China
    4 Department of Chemistry, Zhejiang University, Hangzhou 310027, P. R. China
  • Received:2015-08-24 Published:2016-01-30
  • Contact: Pei-Zhi ZHANG,Jun WU E-mail:zhangpz@zust.edu.cn;wujunwu@zju.edu.cn
  • Supported by:
    the National Natural Science Foundation of China(31471807);Special Fund for Agro-scientific Research in thePublic Interest, China(201403030)

摘要:

研究了酸催化下的2, 6-二甲氧基-2-嘧啶氧基-N-芳基苄胺衍生物Smiles重排反应的动力学,考察了盐酸的初始浓度、溶剂、反应温度和取代基对反应速率的影响。结果表明,盐酸的初始浓度增加,重排反应速率加快;在单一溶剂中反应速率的顺序为:甲醇>乙醇>二甲基亚砜>乙腈,而在甲醇/水(1:1, V/V)的混合溶剂中反应速率明显增加,其表观反应速率常数(kobs)值是甲醇溶剂中的5.27倍;在25-45 ℃温度范围内,各衍生物的反应速率随着温度的升高而加快,其活化能(73.99-76.92 kJ·mol-1)、活化焓(71.57-74.38 kJ·mol-1)及Gibbs自由能(81.51-85.77 kJ·mol-1)数值相近,仅活化熵(-24.38 --47.11 J·K-1·mol-1)有一定的差别;取代基常数和表观速率常数之间呈现一定的线性关系,环上吸电子基团的存在有利于反应速率的提高;实验验证了反应机理的合理性。

关键词: 动力学, 反应机理, 2, 6-二甲氧基-2-嘧啶氧基-N-芳基苄胺衍生物, Smiles重排, 酸催化反应

Abstract:

The kinetics of the acid-catalyzed Smiles rearrangement reactions of 2, 6-dimethoxy-2-pyrimidinyloxy-N-arylbenzylamine derivatives was investigated. The effects of initial concentrations of hydrochloric acid, solvent, temperature, and substituent on reaction rates were examined. The results show that the rates increase with an increase in the initial concentration of hydrochloric acid. The reactivity order is CH3OH > C2H5OH > CH3SOCH3 > CH3CN in a single solvent, but rates markedly increase in mixed CH3OH/H2O (1:1, V/V) and the apparent reaction rate constant (kobs) is 5.27 times that of methanol. The rates for the derivatives are found to increase with an increase in temperature at 25-45 ℃, and no significant differences in activation energy (73.99-76.92 kJ·mol-1), activation enthalpy (71.57-74.38 kJ·mol-1), and Gibbs free energy (81.51-85.77 kJ·mol-1) are observed between them, except that there is difference in activation entropy (-24.38 --47.11 J·K-1·mol-1). There is a good linear relationship between substituents and the apparent reaction rate constants, and it is speculated that electron-withdrawing groups in the benzene ring will increase the reaction rates. A relevant reaction mechanism is suggested.

Key words: Kinetics, Reaction mechanism, 2, 6-Dimethoxy-2-pyrimidinyloxy-N-arylbenzylamine derivatives, Smiles rearrangement, Acid-catalyzed reaction

MSC2000: 

  • O643