Molecular Oxygen Activation by a Copper–Cyamelurate Coordination Polymer for the Selective Oxidation of Benzyl Alcohol

This work reports the synthesis and characterization of a mixed-valence copper–cyamelurate coordination polymer (Cu-CP) prepared through a simple aqueous route from cyamelurate anions derived from the alkaline hydrolysis of g-C₃N₄. The material was characterized by XRD, FTIR, UV–Vis, XPS, SEM, and EPR, confirming the formation of a crystalline coordination polymer with homogeneously distributed copper centers and Cu⁺/Cu²⁺ redox sites. The Cu-CP exhibited high structural stability, negligible copper leaching, and good catalytic performance toward the selective oxidation of benzyl alcohol using molecular oxygen under mild conditions. Mechanistic studies suggest that the catalytic activity is associated with reactive oxygen species generated through Cu⁺/Cu²⁺ redox cycling. These findings indicate that Cu-CP is a promising coordination polymer for selective oxidation using molecular oxygen, combining a sustainable synthesis route, structural stability, and efficient catalytic activity for biomass valorization.