Lead(II) Imides: A New Family of Photoluminescent Heavy Main‐Group Compounds With Oxidatively Induced Nitrene Reactivity

ABSTRACT A new family of low‐valent lead(II) imide dimers, [ R1,R2 ArNPb] 2 ( 1–4 ) ( R1,R2 ArNH 2 = 2,6‐((4‐R 1 ‐C 6 H 4 ) 2 CH) 2 ‐4‐R 2 ‐C 6 H 2 NH 2 ), features a rhombic Pb 2 N 2 core stabilized by short intramolecular Pb⋯Pb contacts and bulky ligands. These complexes exhibit red/near‐infrared solid‐state phosphorescence ( λ max ≈ 730–790 nm) at 77 K, characterized by sub‐microsecond lifetimes and significant ligand‐to‐metal charge‐transfer (LMCT) character. Computational analysis reveals that standard density functional theory (DFT) struggles to capture the energetics of this heavy‐element emission, establishing these systems as critical benchmarks for validating relativistic quantum‐chemical workflows that account for dynamic correlation and spin–orbit coupling. Beyond photophysics, the Pb(II) imides display distinctive nitrene‐transfer and oxidative reactivity; reactions with ortho‐benzoquinones and tetramethylthiuram disulfide yield sterically crowded azobenzenes, rare catecholate‐supported Pb 3 clusters, and sulfur‐rich dimers. The observation that these oxidative transformations quench emission underscores the sensitivity of radiative pathways to the metal coordination environment, positioning these imides as a versatile platform for exploring heavy main‐group reactivity and materials design.