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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]

Catalytic hydrodeoxygenation of bioderived furans is critically attractive to prepare sustainable fuels. Herein, a novel octanediol-route was developed to produce octane through one-pot conversion of bioderived furans at low temperatures. A 96.6% yield of octane was obtained by catalytic conversion with Pd/C and phosphotungstic acid (HPW). Experimental validation of the novel pathway revealed that octanediol intermediates could be formed through hydrogenolysis of furans before deoxygenation. The spontaneous process of this octanediol-route was thermodynamically confirmed by DFT simulations. In addition, characterization studies suggested that water in the system strengthened the cooperation between metals and acids to facilitate C–O bond scission through the modification and hydrogen transfer of HPW. This work highlights a promising reaction pathway for an efficient HDO catalytic system to obtain alkanes from bioderived furans under mild conditions. [ABSTRACT FROM AUTHOR]