A novel method for effecting the aza-Michael reactions of N-alkyl-and N-arylpiperazines with acrylonitrile using Cu-nanoparticles is described. The method features the use of 10mol% Cu (14–17nm) nanoparticles under mild reaction conditions to afford the addition products in good to excellent yields. The Cu-nanoparticles selectively catalysed the aza-Michael reaction of N-alkyl-and N-arylpiperazines in the presence of aromatic amino or aliphatic ...