Isolation and oxygen activation of electron-rich Co II4O metallic clusters having a 3-fold symmetry

Abstract

Two novel atomically precise tetra-nuclear cobalt clusters (3a–3b) having a Co^II₄O core with 3-fold symmetry, and three short Co–Co distances of 2.7046(4) Å are isolated with three chelating NP-donor mono-anionic ligands. 3a–3b are shown to react with O₂, producing dinuclear cobalt complexes (4a–4b), where the P-centres of the ligands are oxygenated. All complexes are structurally characterized by single-crystal X-ray diffraction, and further studied by UV-vis, IR spectroscopy, CV, magnetic susceptibility measurements, and DFT calculations.