Natural Phosphate-Supported Palladium for Hydration of Aromatic Nitriles to Amides in Aqueous Medium

A new generation of natural phosphate-supported palladium was synthesized by treating natural phosphate with bis(benzonitrile)palladium(II) chloride in acetone. Its catalytic activity was evaluated in selective hydration of nitriles. The reactions proceeded in the presence of 0.4 mol% of the palladium catalyst at 160°C in water under microwave irradiation. Several nitriles, including aromatic and heteroaromatic nitriles, were converted to corresponding amides in good yields under neutral conditions. The recyclability and low cost availability of this solid support make this approach very attractive. It encourages new fields of research in the valorization of this natural resource and can change the current view of heterogeneous catalysis.