物理化学学报 >> 2005, Vol. 21 >> Issue (08): 893-897.doi: 10.3866/PKU.WHXB20050814

研究论文 上一篇    下一篇

超临界二氧化碳中卟啉与钴(II)、镍(II)、锌(II)配合物反应动力学

刘士军; 陈启元; 舟桥重信   

  1. 中南大学化学化工学院, 长沙 410083; 名古屋大学化学系, 名古屋, 464-8602, 日本
  • 收稿日期:2004-12-27 修回日期:2005-03-03 发布日期:2005-08-15
  • 通讯作者: 刘士军 E-mail:liushijun@hotmail.com

Kinetic Study of the Reactions of Porphyrin with Co(II), Ni(II) and Zn(II) Compounds in Supercritical Carbon Dioxide

LIU Shi-jun; CHEN Qi-yuan; FUNAHASHI Shigenobu   

  1. College of Chemistry and Chemical Engineering, Central South University, Changsha 410083; Department of Chemistry, Nagoya University, Nagoya 464-8602, Japan
  • Received:2004-12-27 Revised:2005-03-03 Published:2005-08-15
  • Contact: LIU Shi-jun E-mail:liushijun@hotmail.com

摘要: 用紫外-可见光谱研究了钴(II)、镍(II)、锌(II)的1, 1, 1, 5, 5, 5-六氟-2, 4-戊二酮-二水配合物[M(hfac)2(H2O)2, M=Co、Ni、Zn]与5, 10, 15, 20-四(五氟苯基)卟啉[H2tpfpp]在超临界二氧化碳中反应生成金属卟啉[M(tpfpp)]的反应动力学. 在金属配合物大大过量时, 反应对卟啉为一级. 其表观一级速率常数随钴(II)、镍(II)配合物的浓度增加先增加、而后趋于稳定, 而表观一级速率常数随锌(II)配合物的浓度增加线形增加. 根据实验事实, 讨论了反应的机理, 得到了相应的热力学和动力学参数.

关键词: 过渡金属, 卟啉, 超临界二氧化碳, 反应动力学

Abstract: The transition metal ions incorporation reactions into 5, 10, 15, 20-tetrakis (pentafluorophenyl)porphyrin(H2tpfpp) to form the metal porphyrin complexes M(tpfpp) (M= Co, Ni, Zn) have been kinetically investigated using diaquabis(1, 1, 1, 5, 5, 5-hexafluoropentane-2, 4-dionato) metal compounds [M(hfac)2(H2O)2] in supercritical carbon dioxide (scCO2) medium in a spectrophotometric cell. The reactions are first order with respect to H2tpfpp under the conditions where [M(hfac)2(H2O)2] is in large excess relative to H2tpfpp. The saturation dependence of the conditional first-order rate constants as a function of the mole fraction of the excess metal compounds [M(hfac)2(H2O)2] is observed for the reaction systems [Co(hfac)2(H2O)2+H2tpfpp] and [Ni(hfac)2(H2O)2+H2tpfpp], and the linear dependence is observed for the reaction system [Zn(hfac)2(H2O)2+H2tpfpp]. The mechanisms are discussed and the thermodynamic and kinetic parameters for the reactions are obtained.

Key words: Transition metal, Porphyrin, Supercritical CO2, Kinetics