高等学校化学学报 ›› 1999, Vol. 20 ›› Issue (11): 1767.

• 论文 • 上一篇    下一篇

碱性介质中二过碘酸合银(Ⅲ)配离子氧化四氢糠醇的反应动力学及机理

宋文玉, 李文魁, 贾春平   

  1. 河北大学化学系, 保定 071002
  • 收稿日期:1998-12-29 出版日期:1999-11-24 发布日期:1999-11-24
  • 通讯作者: 宋文玉,男,52岁,副教授.
  • 作者简介:宋文玉,男,52岁,副教授.
  • 基金资助:

    河北省自然科学基金

Kinetics and Mechanism of Oxidation of Tetrahydrofurfuryl Alcohol by Diperiodatoargenate(Ⅲ) Complex Ion in Aqueous Alkaline Medium

SONG Wen-Yu, LI Wen-Kui, JIA Chun-Ping   

  1. Department of Chemistry, Hebei University, Baoding 071002, China
  • Received:1998-12-29 Online:1999-11-24 Published:1999-11-24

摘要: 用分光光度法研究了碱性介质中二过碘酸合银(Ⅲ)配离子于27~42℃区间氧化四氢糠醇(THFA)的反应动力学。结果表明,反应对Ag(Ⅲ)及四氢糠醇均为一级,准一级速率常数kobs随[OH-]增大而增大,随[IO4-]增加而减小,并有微弱的正盐效应。在氮气保护下,反应体系不能引发丙烯腈或丙烯酰胺聚合。提出了含有前期平衡的反应机理,求出了平衡常数、速控步骤的速率常数及相应的活化参数。

关键词: 二过碘酸合银(Ⅲ), 四氢糠醇, 氧化还原反应, 动力学及机理

Abstract: The kinetics of oxidation of tetrahydrofurfuryl alcohol by diperiodatoargenate(Ⅲ) complex ion was studied spetrophotometrically in alkaline medium in a temperature range of 27-42 ℃. The reaction rate showed the first order dependance both in oxidant and tetrahydrofurfuryl alcohol. It was found that the pseudo first order ([THFA]》[Ag(Ⅲ)]) rate constant, k obs, increases with the increase in [OH-] and decrease with the increase in [IO4-]ex. Aweak positive ionic strength effect was observed. No free radical was detected. Amechanism of an inner-sphere two-election transfer reaction involving a preequilibrium is proposed. The rate equation derived from the mechanism can be used to explain all the experimental observations. The preequilibrium constants and rate constants of the rate-determining step along with the activation parameters were evaluated.

Key words: Diperiodatoargenate(Ⅲ), Tetrahydrofurfuryl alcohol, Redox reaction, Kinetics and Mechanism

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