高等学校化学学报 ›› 1997, Vol. 18 ›› Issue (3): 434.

• 论文 • 上一篇    下一篇

苯酚过氧化氢羟化过程中Dawson结构钼钒磷杂多化合物的ESR谱研究

郑莹光1, 于剑锋3, 董凤霞1, 杨宇2, 吴通好2, 孙家锺3   

  1. 1. 吉林大学分析测试中心, 长春, 130023;
    2. 吉林大学理论化学研究所, 长春;
    3. 吉林大学分析测试中心化学系, 长春
  • 收稿日期:1996-04-10 出版日期:1997-03-24 发布日期:1997-03-24
  • 通讯作者: 郑莹光, 女, 52岁, 高级工程师.
  • 作者简介:郑莹光, 女, 52岁, 高级工程师.
  • 基金资助:

    国家自然科学基金

Studies on the ESR Spectra of Dawson-Molybdovanadophosphonic Compound in the Process of Phenol Hydroxylation

ZHENG Ying-Guang1, YU Jian-Feng3, DONG Feng-Xia1, YANG Yu2, WU Tong-Hao2, SUN Chia-Chung3   

  1. 1. The Center of Analysis and Testing, Jilin University, Changchun, 13O023;
    2. Department of Chemistry, Jilin University, Changchun, 13O023;
    3. Institute of Theory Chemistry, Jilin University, Changchun, 13O023
  • Received:1996-04-10 Online:1997-03-24 Published:1997-03-24

摘要: 研究了苯酚过氧化氢羟化过程中Dawson结构杂多化合物的ESR谱,通过对比不同反应时间后催化剂的波谱参数,分析了反应过程中V4+→V5+的变化情况.研究结果表明,在反应初期,催化剂仅存在少量V4+,在反应时间达到2h时V4+的含量迅速增多,并出现了V(Ⅰ)及V(Ⅱ)两种波谱参数相异的四价钒,其中V(Ⅰ)对应着V=O键上的V4+,而V(Ⅱ)则对应着加氧中间物种(这里有图片19970323-434-1.gif),反应过程中V(Ⅱ)的含量迅速增多.两种钒均为羟化反应的活性中心.

关键词: Dawson结构杂多化合物, 苯酚羟化, ESR, 四价钒离子

Abstract: ESRspectra of molybdovanadophosphonic compound with Dawson structure in the process of phenol hydroxylation with H2O2 were studied.Contrasting their ESRparameters at different reaction time, the change of V4+V5+ in the system was analyzed.The results indicated that in the initial stage, a few V4+ were produced in the process of the catalyst synthesized.After two hours, the amount of V4+ increased quickly and two kinds of signals of V4+, V(Ⅰ) and V(Ⅱ) appeared-The ESRparameters of V(Ⅰ) were the same as ones at the initial stage, but the signals of V (Ⅰ) were newly appeared.The increasing amount of V(Ⅱ) is higher than that of V(Ⅰ).We had calcuIated the de1ocalized extent of unpaired electrons by the method of Abragam Pryce and assigned that two kinds of V4+, V (Ⅰ) and V(Ⅱ) are all the active centre of the reaction.

Key words: Heteropolycompound with Dawson structure, Hydroxylation of phenol, ESR, V4+ions

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