Hydrogen Bond-Enabled Heterolytic and Homolytic Peroxide Activationwithin Nonheme Copper(II)-Alkylperoxo Complexes

To explore the reactivity of copper-alkylperoxo species enabled by the heterolytic peroxide activation, room-temperature stable mononuclear nonheme copper(II)–alkylperoxo complexes bearing a N-(2-ethoxyethanol)-bis(2-picolyl)amine ligand (HN3O2), [CuII(OOR)(HN3O2)]+ (R = cumyl or tBu), were synthesized and spectroscopically characterized. A combined experimental and computational investigation on the reactivity and reaction mechanisms in the phosphorus oxidation, C–H bond activation, and aldehyde deformylation reactions by the copper(II)–alkylperoxo complexes has been conducted. DFT-optimized structures suggested that a hydrogen bonding interaction exists between the ethoxyethanol backbone of the HN3O2 ligand and either the proximal or distal oxygen atom of the alkylperoxide moiety, and this interaction consequently results in the enhanced stability of the copper(II)–alkylperoxo species. In the phosphorus oxidation reaction, both experimental and computational results indicated that a phosphine-triggered ...