Benzaldehyde Synthesis by the Selective Oxidation of Cinnamaldehyde Catalyzed by Fe ₂ O ₃ ‐modified SBA‐15

Abstract Selective oxidation is one of the primary methods used to synthesize high‐value‐added oxygen‐containing organic compounds from alkenes. In particular, the selective oxidation of natural cinnamaldehyde has gained prominence as one of the main routes to produce natural benzaldehyde, which is in short supply in the global spice market. In this study, FeSBA catalysts were synthesized by supporting Fe 2 O 3 onto the surface of spherical SBA‐15 using pore‐induced deposition for the selective oxidation of cinnamaldehyde to benzaldehyde. The Fe 2 O 3 supporting increased the specific surface area of SBA‐15 by approximately eightfold and significantly improved the utilization efficiency of the reaction sites on Fe 2 O 3 . Additionally, the formation of Fe−O−Si bonds by Fe 2 O 3 and SBA‐15 promoted the generation of weak‐acidic sites on the catalyst surface, significantly increasing the oxygen‐physisorption capacity of Fe 2 O 3 . Furthermore, quenching experiments confirmed the generation of significant amounts of O2 − and singlet‐oxygen species on the FeSBA surface. Theoretical calculations confirmed that the physisorption and chemisorption of cinnamaldehyde and oxygen, respectively, on the FeSBA surface promoted the formation of a tetrameric intermediate. These results contribute significantly to research on the selective oxidation theory of α,β‐unsaturated aldehydes to aldehydes using oxygen and could guide future studies aimed at elucidating and improving the process.