Rhombic Dodecahedral Cu2O-Catalysed Synthesis of Novel Alkenyl Pyrazoles

The design of efficient catalyst is of great importance in pyrazole derivatives synthesis. Herein, rhombic dodecahedra Cu2O microcrystals were successfully synthesized, and employed as catalysts in the direct synthesis of alkenyl pyrazoles. The catalytic activity of the obtained Cu2O catalyst toward the synthesis of alkenyl pyrazoles via the reaction of p-chlorophenyl hydrazone and 2,4-pentanedione was studied. The results showed that the high yields of alkenyl pyrazoles was achieved by using a rhombic dodecahedra Cu2O catalyst. Moreover, the rhombic dodecahedra also exhibited excellent catalytic activity for a variety of different hydrazones, which demonstrates their potential as a versatile catalyst. The Cu2O catalyst shows good reusability. Hence, the rhombic dodecahedra Cu2O microcrystals can be viewed as a highly useful catalyst for synthesis of alkenyl pyrazoles.