Catalytic Ammonia Oxidation to Dinitrogen by a Nickel Complex
Catalytic Ammonia Oxidation to Dinitrogen by a Nickel Complex
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镍络合物催化氨氧化制氮
DOI：
10.1002/anie.202213462
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发表时间：
2022
期刊：
影响因子：
--
通讯作者：
Mock, Michael T.
中科院分区：
文献类型：
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作者：
Stephens, David N.;Szilagyi, Robert K.;Roehling, Paige N.;Arulsamy, Navamoney;Mock, Michael T.
本文报道了一种镍配合物在常温下催化氧化氨制二氮的反应。使用芳氧基自由基2，4，6-三叔丁基苯氧基（tBu 3ArO）作为H原子受体来裂解配位的NH3配体的N-H键，可以产生每个Ni中心高达56当量的N2。 采用N-氧基自由基2，2，6，6-（四甲基哌啶-1-基）氧基（克里思）作为H-原子受体，每个Ni中心形成高达15当量的N2。 通过同位素氮（15 N）研究确定的桥接镍-肼产物并得到计算模型的支持，表明N-N键形成步骤是通过两个顺磁性[Ni]− NH 2片段的顺磁性偶联发生的。Ni介导的肼分解为N2和NH3完成催化循环。
We report a nickel complex for catalytic oxidation of ammonia to dinitrogen under ambient conditions. Using the aryloxyl radical 2,4,6‐tri‐tert‐butylphenoxyl (tBu3ArO⋅) as a H atom acceptor to cleave the N−H bond of a coordinated NH3ligand up to 56 equiv of N2per Ni center can be generated. Employing theN‐oxyl radical 2,2,6,6‐(tetramethylpiperidin‐1‐yl)oxyl (TEMPO⋅) as the H‐atom acceptor, up to 15 equiv of N2per Ni center are formed. A bridging Ni‐hydrazine product identified by isotopic nitrogen (15N) studies and supported by computational models indicates the N−N bond forming step occurs by bimetallic homocoupling of two paramagnetic [Ni]−NH2fragments. Ni‐mediated hydrazine disproportionation to N2and NH3completes the catalytic cycle.