Aromatic Hydroxylation at a Non-Heme Iron Center: Observed Intermediates and Insights into the Nature of the Active Species
作者:Olga V. Makhlynets、Elena V. Rybak-Akimova
DOI:10.1002/chem.201002577
日期:2010.12.17
highly reactive, biomimetic, iron aminopyridine complex, [FeII(bpmen)(CH3CN)2][ClO4]2 (1; bpmen=N,N'‐dimethyl‐N,N'‐bis(2‐pyridylmethyl)ethane‐1,2‐diamine), is elucidated. Complex 1 has been shown to be an excellent catalyst for epoxidation and functional‐group‐directed aromatic hydroxylation using H2O2, although its mechanism of action remains largely unknown.1, 2 Efficient intermolecular hydroxylation
在高反应活性,仿生铁氨基吡啶络合物[Fe II(bpmen)(CH 3 CN)2 ] [ClO 4 ] 2(1 ; bpmen = N,N'-二甲基- ñ,ñ “ -双(2-吡啶基甲基)乙烷-1,2-二胺),被阐明。络合物1已被证明是使用H 2 O 2进行环氧化和官能团定向的芳香族羟基化反应的极佳催化剂,尽管其作用机理尚不清楚。1, 2在本工作中发现了在1存在下未官能化的苯和取代的苯被H 2 O 2有效地分子间羟基化的现象。报道了有关铁(III)-酚盐产物形成的详细机理研究。我们已经确定,以高收率生成,并且实验其特征在于所述键的Fe III(OOH)中间体(λ最大= 560纳米,菱形EPR信号与克= 2.21,2.14,1.96)由形成1和H 2 ö 2。停止流动力学研究表明,Fe III(OOH)不会直接羟基化芳环,但会发生限速自分解,从而产生瞬态反应性氧化剂。酸辅助氢-过氧化铁中间体