The search for a highly active nitrido complex that can transfer its nitrogen atom to inert organic molecules remains a challenge to chemists. In this regard, the use of solar energy to generate a reactive nitrido species is an appealing strategy to solve this problem. Here we report the design of a strongly luminescent osmium(VI) nitrido compound, [OsVI(N)(NO2-L)(CN)3]− (NO2-OsN) with emission quantum yield (Φ) and life time (τ) of 3.0% and 0.48 μs, respectively in dichloromethane solution. Upon irradiation with visible light, this complex readily activates the aliphatic C-H bonds of various hydrocarbons, including alkanes. The excited state of NO2-OsN can undergo ring-nitrogenation of arenes, including benzene. Photophysical and computational studies suggest that the excited state of NO2-OsN arises from O^N ligand to Os ≡ N charge transfer transitions, and as a result it possesses [Os = N•] nitridyl character and is highly electrophilic.

The utilization of triplet metal‐metal‐to‐ligand‐charge‐transfer (3MMLCT) emissions of Pt(II) complexes having a large radiative decay rate is a promising strategy to develop efficient red and deep‐red emitters for practical organic light‐emitting diodes (OLEDs). The panel of robust luminescent dinuclear Pt(II) emitters described here features pyridine‐/pyrazine‐fused N‐heterocyclic carbene‐based cyclometalating ligands and ditopic bis‐µ2‐formamidinate bridging ligands. These complexes show intramolecular Pt–Pt distances of 2.85–2.87 Å, are thermally stable up to 446 °C, and display strong red and deep‐red 3MMLCT emission (604–689 nm) with emission quantum yields close to unity. Under laboratory conditions, red and deep‐red OLEDs with these complexes show high external quantum efficiencies (up to 21.3%) and prolonged operational lifetimes (LT97 up to 2446 h) at an initial luminance of 1000 cd m−2, highlighting the practicality of these dinuclear Pt(II) emitters in organic optoelectronics application.

The development of novel luminescent iridium(III) complexes with highly tunable emission energy and versatile applications is of particular importance. In this Communication, a series of luminescent iridium(III) complexes supported by chromophoric pyridinium-derived N-heterocyclic carbene (NHC) ligands that display tunable emission from 516 to 682 nm were prepared. These complexes can be used as photocatalysts in photooxidation and photoreduction reactions and could have potential applications in pH sensing.