Salen complex of Cu (II) supported on superparamagnetic Fe3O4@SiO2 nanoparticles: an efficient and magnetically recoverable catalystfor the Synthesis is of 4-dihydropyridines

The Fe3O4@SiO2/Salen-Cu(II) nanocatalyst is reported as a thermally and air-stable, economical, and magnetically recoverable heterogeneous catalyst for the selective and efficient 1,4-dihydropyridines Fig. 1. Only by adding a small amount of the catalyst (0.4mol% Cu) to the reactants and heating under air, the new presented method provides a variety of functionalized 1, 4-dihydropyridines in good to excellent yields within short reaction times.1 The catalyst could be easily recovered with the aid of a permanent magnet and reused up to five consecutive runs without significant loss of activity. Also, the leaching of Cu was negligible after the fifth recycle.2 Particularly, ethyl acetoacetate and aromatic aldehydes as agents and the need of only small amount of the magnetically recoverable heterogeneous copper-based nanocatalyst make this method low-cost, environmentally benign, and easy to use.3

کلیدواژه ها:

Nanocatalyst ، 4-Dihydropyridines ، Hantzsch Synthesis ، Salten