Synthesis of Pyrimidin derivatives using Fe3O4@Ag-β-CD nanoparticles as a green and magnetically recyclable nanocatalyst

Insolubility of most organic substances in water as well as the distribution or deactivation of many active substrates, reagents, and catalysts by water molecules are the two significant limitations of organic reactions in aqueous media [1]. To overcome these constraints, there are some strategies that facilitate the use of water as a solvent for a wide variety of organic reactions. β-CD forms inclusion complexes with smaller molecules and they can be exist in aqueous solution. The hydrophobic cavity of the β-CD allows this molecule to encapsulate a variety of non-polar molecules of suitable size [2]. Ag nanoparticles have been recently shown to be efficient catalyst for some important reactions [3]. In the present paper, Ag-β-CD nanoparticles have been successfully linked on the surface of magnetic Fe3O4 nanoparticles. The morphology, composition and crystallinity of the Fe3O4@Ag-β-CD nanocomposites were characterized by FT-IR, XRD, TEM and EDS techniques. This new catalyst was employed for one-pot synthesis of pyrimidin derivatives in aqueous solution under mild conditions (Scheme). Compared with the classical Biginelli reactions this procedure showed several advantages including mild reaction conditions with environmental benign, excellent yields, short reaction times, and also this catalyst can be recovered easily and reused many times without significant loss of its catalytic activity.