C–H Oxidation by H<sub>2</sub>O<sub>2</sub> and O<sub>2</sub> Catalyzed by a Non-Heme Iron Complex with a Sterically Encumbered Tetradentate N-Donor Ligand
作者:Qiao Zhang、John D. Gorden、Christian R. Goldsmith
DOI:10.1021/ic402501k
日期:2013.12.2
substrates, the neopentyl groups destabilize the metal-based oxidants generated from H2O2 and the Fe(II) complex. The presence of benzylic substrates with weak C–H bonds stabilizes an intermediate which we have tentatively assigned as a high-spin ferric hydroperoxide species. The oxidant generated from O2 reacts with allylic and benzylic C–H bonds in the absence of a sacrificial reductant; less substrate
的化合物Ñ,N' -dineopentyl- Ñ,Ñ ' -双(2-吡啶基甲基)-1,2-乙二胺(dnbpn)及其亚铁复杂的[Fe(dnbpn)(OTF)2 ]合成的。Fe(II)络合物用于催化H 2 O 2和O 2氧化烃。尽管H 2 O 2催化了烷烃的氧化与大多数先前报道的非血红素铁催化剂相关的那些相比,对叔碳显示出对仲碳而不是叔碳的更高的偏好,催化活性显着降低。除了将催化的氧化导向底物的较少拥挤的C–H键外,新戊基还使由H 2 O 2和Fe(II)络合物生成的金属基氧化剂不稳定。具有弱C–H键的苄基底物的存在稳定了一种中间体,我们暂时将其定为高纺氢过氧化铁物种。由O 2产生的氧化剂在不存在牺牲性还原剂的情况下与烯丙基和苄基CH键反应;与使用O 2作为末端氧化剂的相关先前描述的系统相比,观察到的底物脱氢更少。