Thermally-Stable Single-Site Pd on CeO2 Catalyst for Selective Amination of Phenols to Aromatic Amines without
Yaqin Wang1,2, Bingfeng Chen3, Lina Li4
1Shanghai Key Laboratory of Green Chemistry and Chemical Processes, State Key Laboratory of Petroleum Molecular & Process Engineering, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, 200062, P. R. China E-mail:E-mail.
Abstract:
Developing a new route to produce aromatic amines as key chemicals from renewable phenols is a benign alternative to current fossil-based routes like nitroaromatic hydrogenation, but is challenging because of the high dissociation energy of the Ar-OH bond and difficulty in controlling side reactions. Herein, an aerosolizing-pyrolysis strategy was developed to prepare high-density single-site cationic Pd species immobilized on CeO2 (Pd1/CeO2) with excellent sintering resistance. The obtained Pd1/CeO2 catalysts achieved remarkable selectivity of important aromatic amines (yield up to 76.2 %) in the phenols amination with amines without external hydrogen sources, while Pd nano-catalysts mainly afforded phenyl-ring-saturation products. The excellent catalytic properties of the Pd1/CeO2 are closely related to high-loading Pd single-site catalysts with abundant surface defect sites and suitable acid-base properties. This report provides a sustainable route for producing aromatic amines from renewable feedstocks.
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