Lian Wengao, Xu Hengyue, Zou Xingyue, Dai Jie, Li Meiqi, Ling Cancan, Shen Yunhao, Li Hao, Yao Yancai, Zhang Lizhi
State Key Laboratory of Green Papermaking and Resource Recycling, National observation and Research Station of Erhai Lake Ecosystem in Yunnan, Yunnan Dali Research Institute, School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, P. R. China.
Department of Chemistry, Tsinghua University, Beijing, P. R. China.
Nat Commun. 2025 Jul 1;16(1):5989. doi: 10.1038/s41467-025-60919-7.
Surface high-valent iron-oxo species (≡Fe=O) are reliable and green oxygen atom transfer reagents, but the ability is seriously inhibited by the maximal orbital overlap of axial Fe = O double bond in a symmetric planar coordination environment. Herein, we report the synthesis of planar asymmetric surface Fe = O (PA-≡Fe = O) on pyrite using chlorite as the oxidant, where the in-situ generated ClO can transform a planar Fe-S bond to Fe-Cl by oxidizing and subsequently substituting planar sulfur atoms. Different from planar symmetric surface Fe = O (PS-≡Fe = O) with electron localization around axial Fe = O, PA-≡Fe = O delocalizes electrons among Fe, axial oxo moiety and its planar ligands owing to the stronger electron-withdrawing capacity of Cl, which effectively weakens the orbital overlap of axial Fe = O bonding and thus facilitates the rapid electron transfer from the substrates to the unoccupied antibonding orbital of PA-≡Fe = O, realizing more efficient oxygen atom transfer oxidation of methane, methyl phenyl sulfide, triphenylphosphonate and styrene than PS-≡Fe = O. This study offers a facile approach for the synthesis of planar asymmetric surface Fe = O, and also underscores the importance of planar coordination environment of high-valent metal-oxo species in the oxygen atom transfer reactions.
表面高价铁氧物种（≡Fe=O）是可靠的绿色氧原子转移试剂，但在对称平面配位环境中，轴向Fe=O双键的最大轨道重叠严重抑制了其活性。在此，我们报道了以亚氯酸盐为氧化剂在黄铁矿上合成平面不对称表面Fe=O（PA-≡Fe=O）的方法，原位生成的ClO可通过氧化并随后取代平面硫原子，将平面Fe-S键转化为Fe-Cl键。与轴向Fe=O周围电子定域的平面对称表面Fe=O（PS-≡Fe=O）不同，由于Cl更强的吸电子能力，PA-≡Fe=O使电子在Fe、轴向氧部分及其平面配体之间离域，有效减弱了轴向Fe=O键的轨道重叠，从而促进了底物向PA-≡Fe=O未占据反键轨道的快速电子转移，实现了比PS-≡Fe=O更高效的甲烷、苯甲硫醚、三苯基膦酸酯和苯乙烯的氧原子转移氧化反应。本研究为平面不对称表面Fe=O的合成提供了一种简便方法，也强调了高价金属氧物种平面配位环境在氧原子转移反应中的重要性。
