Synthesis and Characterization of High Valnet Reaction Intermediate of Non-Heme Iron Enzymes

高价铁氧物种被认为是血红素铁酶和非血红素铁酶催化氧化反应的关键反应中间体。在血红素酶的情况下，卟啉模型化合物已被广泛研究，氧铁(IV)卟啉π-阳离子自由基被表征为最有可能的活性物种。然而，目前还不清楚这种高价铁氧物种是否是由单核非血红素铁活性中心产生的，在这些活性中心中没有电子池可以取代卟啉环的大π-共轭。因此，从单核非血红素铁模型络合物中制备瞬时氧化物种是值得挑战的，以便与血红素情况进行比较，详细研究电子结构。为此，我们制备了一种含间苯基取代基的Salen铁络合物，作为单核铁酶的模型。我们还试图制作一种由空间受阻的Salen铁络合物和间氯过氧苯甲酸(MCPBA)生成的暂态中间体。

High-valent iron-oxo species are proposed to be the key reactive intermediate in oxidation reactions catalyzed by both heme and non-heme iron enzymes. In the case of heme enzymes, porphyrin model complexes have been extensively investigated, and oxo-iron (IV) porphyrin π-cation radical have been characterized as the most probable candidate for the active species. However, it is still unclear whether such high-valent iron-oxo species are generated from mononuclear non-heme iron active sites, in which there is no electron pool that can replace the large π-conjugation of the porphyrin ring. It is thus worth challenging to prepare transient oxidizing species from a mononuclear non-heme iron model complex for a detailed study of the electronic structure in comparison with the heme case. To this end, we have prepared a salen iron complex having a mesityl substituent, as a model for mononuclear iron enzymes. We have also tried to make a transient intermediate generated from the sterically hindered salen iron complex and m-chloroperoxybenzoic acid (mCPBA).