Abstract:

Bimetallic metal-organic frameworks（MOFs） possess tunable skeletal structures and synergistic effects between multiple metals， demonstrating significant application potential in the field of catalysis. In this study， Cu²⁺ and Co²⁺， which have similar electronic structures and ionic radii， were selected as metal centers to successfully construct a bimetallic CuCo-MOF catalyst， achieving efficient and mild air-mediated epoxidation of cycloalkenes without the addition of external initiators or co-reductants. The Cu_0.1Co-MOF-BTC-S-150-24 catalyst prepared via static hydrothermal method was characterized by X-ray diffraction（XRD）， field emission scanning electron microscope（FESEM）， X-ray photoelectron spectroscopy（XPS） and NH₃-temperature programmed desorption（NH₃-TPD）. Under optimized conditions（using 1，4-dioxane as the solvent， 80 °C， 5 h， and air as the oxidant）， the catalyst demonstrates excellent catalytic performance in the air-catalyzed epoxidation of 3-methyl-1-cyclohexene， achieving a substrate conversion rate of up to 97.2% and epoxide product selectivity ≥99%. Additionally， the catalyst demonstrates good substrate universality， achieving conversion rates of 79.4% and 80.3% for cyclooctene and 4-vinyl-1- cyclohexene， respectively， with corresponding epoxide product selectivities of 98.0% and 74.3%. After five cycles of use， the catalyst maintains stable catalytic activity， indicating excellent cyclic stability.

Key words: Bimetallic CuCo-MOFs, Cycloolefin, 3-Methyl-1-cyclohexene, Air, Epoxidation