A series of Pd-based intermetallic compounds (ordered alloys) supported on SiO
2 were prepared and used for the aerobic oxidation of amines to imines. Pd
3Pb/SiO
2 showed a remarkably higher catalytic activity than monometallic Pd/SiO
2. Increase in basicity of catalyst support further enhanced the catalytic activity of Pd
3Pb. Nanoparticulate Pd
3Pb supported on Al
2O
3 can act as a highly efficient heterogeneous catalyst for the oxidation of various amines including primary, secondary, aromatic, aliphatic, and cyclic amines. A kinetic study revealed that the enhanced catalytic activity of Pd
3Pb was attributable to the promotion of imine desorption, which was the rate-determining step for the Pd catalyst. The enhancement in catalytic activity of Pd
3Pb with the basicity of support was attributed to the promotion of amine adsorption due to deprotonation by basic sites.
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