Copper nanoparticles assembled on carboxymethylcellulose (Cu0NPs@CMC) were successfully synthesized and well characterized by FT-IR, SEM, EDS, TEM, XPS, and ICP-AES. The new prepared nanocatalyst was applied effectively as a heterogeneous catalyst for the synthesis of propargylamines via decarboxylatived A3 and classic A3 reaction under solvent-free condition. A broad spectrum of diversely polysubstituted propargylamines could be obtained in moderate to excellent yields. The present method showed several merits such as easy work-up, short reaction time, additive-free characteristic, solvent-free condition, functional group tolerance, usage of recyclable green and sustainable nanocatalyst. [ABSTRACT FROM AUTHOR]