iron-oxo species have frequently been invoked in the oxidation of hydrocarbons by both heme and non-heme enzymes. Although a formally Fe(V)=O species, that is, [(Por(*))Fe(IV)=O](+), has been widely accepted as the key oxidant in stereospecific alkane hydroxylation by heme systems, it is not established that such a high-valent state can be accessed by a non-heme ligand environment. Herein we report a systematic
血红素和非血红素酶在碳氢化合物的氧化中经常调用高价
铁氧类物质。尽管形式上的 Fe(V)=O 物种,即 [(Por(*))Fe(IV)=O](+) 已被广泛接受为血红素系统立体有择
烷烃羟基化的关键氧化剂,但它是尚未确定非血红素
配体环境可以访问这种高价态。在此,我们报告了对由一组非血红素
铁配合物催化的 H(2)O(2)
烷烃氧化的系统研究,即 [Fe(II)(
TPA)(CH(3)CN)(2) ](2+) (1,
TPA = tris(2-pyridylmethyl)amine) 及其α-和β-取代的类似物。该系列 Fe(II)(
TPA) 催化剂的反应模式可以通过
配体环境的电子和空间特性进行调节,这会影响常见的 Fe(III)-OOH 中间体的自旋态。当
TPA 配体具有两个或三个 α 取代基时,这种 Fe(III)-过氧物种是高自旋的,并且被提议直接负责
烷烃底物的选择性 CH 键断裂。然而,由