Nano-size ZnS: A novel, efficient and recyclable catalyst for A3-coupling reaction of propargylamines

•Preparation of nanosize ZnS and analyzed by SEM, TEM, and XRD.•Synthesis of diverse Propargylamines by A3 coupling reactions of aldehydes, amines and alkynes via CH activation.•Catalyst is an efficient renewable eco friendly, reusable and easily separated from the products.

Nano-size ZnS was prepared by a simple, economic and elegant chemical bath deposition technique and characterized by using SEM, TEM, XRD, and EDAX techniques. Prepared nano-size ZnS was found to be highly efficient novel heterogeneous catalyst for A3-coupling reaction of Propargylamines (4a–4l) using various aldehydes, amines and terminal alkyne groups through CH activation. The catalyst was recycled more than eight consecutive cycles and reused in the subsequent reactions without any loss in its activity. The developed protocol offers efficient synthesis of diverse propargylamines without using co-catalyst and any other activator, high catalytic activity and short reaction times were obtained when compared to other metal ion and/or metal oxide catalysts.

Graphical abstractA new and efficient method has been developed for the synthesis of Propargylamines (4a–4l) using A3-coupling reaction of various aldehydes, amines and terminal alkyne groups through CH activation. The developed protocol offers efficient synthesis of diverse Propargylamines without using co-catalyst and any other activator.Figure optionsDownload full-size imageDownload high-quality image (90 K)Download as PowerPoint slide