Impact of Fluorinated Cobalt(II) Phthalocyanine Catalysts on Aerobic Thiol Oxidation Kinetics
Impact of Fluorinated Cobalt(II) Phthalocyanine Catalysts on Aerobic Thiol Oxidation Kinetics
复制标题
氟化钴(II)酞菁催化剂对硫醇好氧氧化动力学的影响
DOI：
10.1080/00986445.2015.1067802
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发表时间：
2015
影响因子：
2.5
通讯作者：
R. Barat
中科院分区：
文献类型：
--
作者：
N. Reid;R. Barat
研究了酞菁钴H16 PcCo、F16 PcCo和F64 PcCo催化2-巯基乙醇（2-ME）和4-氟苯乙烷（4-FBT）的有氧氧化动力学。实验在反应受限的等温实验室规模间歇反应器中进行，硫醇浓度使用GC/FID测量。2-ME转化为2-羟乙基二硫醚，4-FBT转化为4-氟苯基二硫醚，转化率超过90%。动力学分析表明，底物结合和电子转移与催化剂分子的刘易斯酸性和空间体积有直接关系。底物结合被认为是缓慢的步骤，硫醇氧化催化H16酞菁钴。F16 PcCo和F64 PcCo催化的硫醇氧化反应的速率控制步骤是从催化剂分子中排出巯基自由基（RS·）。
Kinetic studies were conducted for the aerobic oxidation of 2-mercaptoethanol (2-ME) and 4-fluorobenzenethiol (4-FBT) catalyzed by cobalt(II) phthalocyanines: H16PcCo, F16PcCo, and F64PcCo, each exhibiting a metal center subject to increasing Lewis acidity and steric hindrance. The experiments were performed in a reaction-limited, isothermal, bench-scale, batch reactor, with thiol concentrations measured using GC/FID. Conversions of 2-ME to 2-hydroxyethyl disulfide and 4-FBT to 4-fluorophenyl disulfide in excess of 90% were achieved. Kinetic analyses suggest that the substrate binding and electron transfer are directly related to the Lewis acidity and steric bulkiness of catalyst molecules. Substrate binding was found to be the slow step for thiol oxidations catalyzed by H16PcCo. The rate-determining step for thiol oxidations, catalyzed by F16PcCo and F64PcCo, is the expulsion of the thiyl radical (RS•) from the catalyst molecule.