Here, we report a novel preparation of copper nanoparticles in ionic liquid and its use in the addition elimination reaction. Powder X-ray diffraction, transmission electron microscopy and quassi elastic light scattering techniques revealed the formation and size of copper nanoparticles and its use for the addition-elimination reaction between active methylene compounds and imines using an ionic liquid in presence of NEt3 to yield the corresponding products in high yields and in short duration was done.