Metallonitrenes (M–N) are complexes with a subvalent atomic nitrogen ligand that have been proposed as key reactive intermediates in nitrogen atom transfer reactions. However, in contrast to the common classes of nitride complexes (M≡N) and organic nitrenes (R–N), structurally and spectroscopically well defined ‘authentic’ metallonitrenes with a monovalent atomic nitrogen ligand remain elusive. Here we report that the photolysis of a platinum(ii) pincer azide complex enabled the crystallographic, spectroscopic, magnetic and computational characterization of a metallonitrene that is best described as a singly bonded atomic nitrogen diradical ligand bound to platinum(ii). The photoproduct exhibits selective C–H, B–H and B–C nitrogen atom insertion reactivity. Despite the subvalent metallonitrene character, mechanistic analysis for aldehyde C–H amidation shows nucleophilic reactivity of the N-diradical ligand. Ambiphilic reactivity of the metallonitrene is indicated by reactions with CO and PMe₃ to form isocyanate and phosphoraneiminato platinum(ii) complexes, respectively.

Metallonitrenes (M-N) 是与亚价原子氮配体的配合物，已被提议作为氮原子转移反应中的关键反应中间体。然而，与常见类别的氮化物配合物 (M≡N) 和有机氮烯 (R-N) 相比，结构和光谱上明确定义的具有单价原子氮配体的“真实”金属氮烯仍然难以捉摸。在这里，我们报告铂 ( ii ) 钳叠氮化物配合物的光解使金属硝烯的晶体学、光谱学、磁性和计算表征成为可能，最好将其描述为与铂 ( ii)结合的单键原子氮双自由基配体）。光产物表现出选择性的 C–H、B–H 和 B–C 氮原子插入反应性。尽管具有亚价金属氮烯特性，醛 C-H 酰胺化的机理分析显示 N-双自由基配体的亲核反应性。通过与CO和PMe ₃反应分别形成异氰酸酯和亚磷酰胺铂( ii )配合物，表明金属氮烯的两亲反应性。