The Hydrogenation of Aromatic Compounds under Mild Conditions by Using a Solid Lewis Acid and Supported Palladium Catalyst

Al2O3 or SiO2 particles with abundant surface hydroxyl groups can prevent side reactions of aromatic compounds with AlCl3 completely; this Lewis acid can potentially destroy the stable structure of aromatic compounds to a large extent. This discovery was successfully utilized in the highly efficient hydrogenation of benzene, toluene, and naphthalene under mild conditions co‐catalyzed by AlCl3 and Pd/Al2O3 or Pd/SiO2. Pd, AlCl3, and the surface hydroxyl groups on the support show excellent cooperative effects for the hydrogenation reactions. Theoretical studies indicate that formation of a complex, by an interaction between benzene, AlCl3, and the solid oxides, plays a key role in the highly efficient hydrogenation reactions.