The synthesis and characterization of new copper(II)-L-3,4-dihydroxyphenyylalanine based magnetically separable nanocatalyst, namely Fe3O4@L-DOPA@Cu-II (L-DOPA = L-3,4-dihydroxyphenyylalanine), are described. The catalyst has been characterized by physicochemical studies. We have studied the application of this new catalyst for asymmetric aza-Michael addition reaction. This catalyst could simply be separated and recovered from the reaction mixture with the assistance of an external magnet and reused several times. (C) 2016 Elsevier B.V. All rights reserved.