Se Nanoparticle-Catalyzed Selective C(OH)–C Bond Cleavage for Ester and Amide Synthesis: Contrasting Inactivity of Single-Atom Se Sites

The selective cleavage and functionalization of inert C(OH)–C bonds are critical steps in the valorization of renewable biomass into high-value chemicals. However, current catalytic strategies often rely on metal-based additives or harsh conditions. Herein, we report a recyclable, metal-free catalytic system composed of selenium nanoparticles supported on nitrogen-doped carbon nanosheets (SeNPs@CNs), which enables the aerobic oxidative cleavage of C(OH)–C bonds to esters and amides under mild, additive-free conditions. The catalyst exhibits broad substrate compatibility─including sterically hindered aryl alcohols and β-O-4 lignin model compounds─and maintains activity on the gram scale. Mechanistic control and characterization studies reveal that selenium nanoparticles, rather than atomically dispersed Se species, are responsible for the observed activity due to their more favorable substrate adsorption and oxygen activation properties. This work establishes selenium nanostructures as an environmentally benign and mechanistically distinct platform that complements existing transition-metal systems for sustainable organic synthesis.