期刊
ACS CATALYSIS
卷 11, 期 18, 页码 11754-11761出版社
AMER CHEMICAL SOC
DOI: 10.1021/acscatal.1c03087
关键词
molybdenum complexes; perchlorate reduction; bioinspired; oxygen atom transfer; homogeneous catalysis
资金
- NAWI Graz
Two molybdenum(VI) complexes act as catalysts for the reduction of (per)chlorate, with the pyrimidine-2-thiolate system showing higher efficiency. The reduction of (per)chlorate to chloride is facilitated by the catalysts, with the initial oxygen atom transfer from [MoO2L2] to PPh3 being the rate-determining step.
Inspired by the reactivity of (per)chlorate reducing molybdoenzymes and encouraged by the lack of molybdenum-containing functional models thereof, two molybdenum(VI) complexes of the type [MoO2L2] (L = pyrimidine-2-thiolate or 6-methylpyridine-2-thiolate) were found to be active homogeneous catalysts for the reduction of ClO4- to ClO3- in CH2Cl2 using PPh3 as sacrificial oxygen acceptor. The subsequent stepwise reduction of ClO3- to Cl- is facilitated by our catalysts, but it can also proceed with only PPh 3 without the aid of a catalyst. We followed the decrease in perchlorate concentration in the catalytic solutions not only indirectly by oxidation of PPh3 to OPPh3 via H-1 NMR spectroscopy but also directly by determining the perchlorate concentration at certain time points over 24 h with high-performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICPMS/MS). These experiments revealed the pyrimidine-2-thiolate system to be more efficient. The reduction of ClO4- to ClO3- with [MoOL2], which is generated after the reaction of [MoO2L2] with PPh3, was computed to be highly exergonic with low kinetic barriers for both catalysts. Thus, the rate-determining step of the overall catalytic reaction is the initial oxygen atom transfer from [MoO2L2] to PPh3.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据