Impregnated Antimony on NiFe2O4: An Efficient Magnetically Separable Nanocatalyst for Rapid Acylation of Amines

Selective protection of amines is one of the most important methods for multistep synthesis of organic compounds [1-2]. In this context, more attention has been paid to core–shell nano systems with the core of magnetite. They are simply prepared and because of their good magnetic properties are easily removed from the reactions. Functionalized magnetic nanoparticles (MNPs) are robust, air-stable and frequently used for immobilization of various heterogeneous [3-6] and homogenous catalysts. These subjects prompted us to prepare NiFe2O4/Sb as an efficient and reusable nanocatalyst toward acetylation of arylamines with Ac2O in H2O (Scheme 1). Remarkable reusability and easy separation of the nanocatalyst, high yields and mild reaction condition as well as the benefits of using water as a green solvent are the advantages which make this protocol a perfect candidate for the acetylation of amines