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Creators/Authors contains: "Stephens, David N"

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  1. ; ; ; ; (, Chemical Communications)
    Fac-[(CO)3Mo(PtBu2NPh2)(NH3)] catalyzed NH3oxidation to N2using phenoxyl radicals as H atom acceptors generating up to 88 equiv. N2per Mo centre. 
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    Free, publicly-accessible full text available June 2, 2026
  2. ; ; ; ; (, Angewandte Chemie International Edition)
    Abstract 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. 
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