Synthesis of Allyl Ethers from Allyl Chloride with Alcohols Catalyzed by Copper-Zirconium Oxide Supported PdO

A series of copper-zirconium oxides with the Cu/Zr ratio ranging from 2/8 to 9/1 were synthesized by the co-precipitation method. The PdO/CumZrn catalysts were prepared and applied to synthesis of allyl ethers via the etherification reactions of allyl chloride with alcohols. The characterization results demonstrated that the presence of ZrO2 phase not only can facilitate the high dispersion of Pd2+, but can also favor the formation of Cu+ via the interaction between CuO and ZrO2. The catalytic performance initially increases and then falls off with the progressive increase in the Cu/Zr ratio. The superior performance with a conversion of 53.2% along with a selectivity of 60.3% was achieved over the resulting PdO/ Cu7Zr3 catalyst with the highest surface molar proportion of Cu+. Good catalytic activity was obtained, because the Cu+-O alpha- pairs could enhance the dissociative activation of the -O-H bond in alcohols compared with Cu-2(+)-O2- pairs, subsequently promoting the etherification reactions.