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Synthesizing fine chemicals and valuable pharmaceutical intermediates through selective catalytic oxidation of alcohols is indispensable and crucial. However, the conventional methods of alcohol oxidation have inevitable drawbacks, including harsh reaction conditions and environmental pollution. Thus, it is imperative to develop efficient catalytic oxidation systems for alcohols. Herein, we successfully synthesized a 15 wt %PI‐TiO2 composite by a one‐step solid‐state heating polymerization technique. This catalyst exhibits excellent responsiveness to visible light and demonstrates remarkable catalytic activity. Furthermore, TEMPO was introduced as a cocatalyst to construct a PI‐TiO2/TEMPO/O2 system for the catalytic oxidation of alcohols. In comparison to the individual effects of PI or TiO2, this system showcases improved catalytic activity and broader substrate applicability. As a result, the conversion efficiency of benzyl alcohol increases by 3.44 times and 2.26 times, respectively. This research not only introduces a novel approach for preparing visible light‐active PI‐TiO2 catalysts but also indicates the significance of establishing an efficient electron transfer process in alcohol catalytic oxidation. [ABSTRACT FROM AUTHOR]

Selective cleavage of C–C bonds in the lignin structure is crucial for the depolymerization of lignin and producing value-added chemicals. In this study, we reported that Pd/CeO2 catalysts can selectively catalyze the Cα–Cβ bond cleavage of oxidized lignin model components and authentic lignin in an aqueous phase under mild conditions (50 °C, ambient pressure). A variety of β-O-4 and β-1 ketones with representative Cα–Cβ bonds were successfully cleaved yielding aromatic acids and phenols in 76.8–94.9% yields. Their unique catalytic properties are derived from the electron transfer between Pd and CeO2 support which facilitates active Pd2+ sites and reactive oxygen species formation. A mechanistic study elucidates that base-mediated C–H bond activation via enolization and in situ reactive oxygen species (˙O2−) formation are the key steps for the selective Cα–Cβ cleavage. Furthermore, the applicability of the system for the bond cleavage in an authentic lignin sample was demonstrated. Nearly 54.2 wt% of oxidized bamboo lignin was converted, generating aromatic monomer yields up to 35.9 wt%, with a high selectivity for aromatic aldehydes. [ABSTRACT FROM AUTHOR]