Eggshell-supported-Cu(II) salophen complex: An efficient and green catalyst for synthesis of propargylamines under solvent-free conditions

In this report, the synthesis, characterization, and application of the eggshell-supported-Cu(II) salophen complex, as a novel and heterogeneous catalyst, is described. The catalyst is characterized by the UV, XRD, FT-IR, and SEM techniques. The eggshell-supported-Cu(II) salophen complex is a versatile, green, inexpensive, and simple catalyst used for the multicomponent reactions (MCRs) of terminal alkynes, aldehydes, and secondary amines to give the corresponding propargylamines at 80 °C under the solvent-free conditions. The proposed methodology offers several advantages such as excellent product yield, simple procedure, and mild conditions. On the other hand, the synthesized catalyst could be removed from the reaction mixture by simple filtration and reused for up to six runs.