Synthesis and applications of CoFe2O4 nanoparticles for multicomponent reactions

An efficient, simple, green protocol is developed for the synthesis of 2-amino-4-(phenyl)-5,6,7,8-tetrahydro-7,7-dimethyl-5-oxo-4H-chromene-3-carbonitrile derivatives and 2,2'-arylmethylene bis(3-hydroxy-5,5-dimethyl-2-cyclohexene-1-one) derivatives in the presence of CoFe2O4 nanoparticles in aqueous ethanol medium. CoFe2O4 nanoparticles have been synthesised by a co-precipitation method followed by ultrasonication. The synthesised CoFe2O4 nanoparticles have high surface area (140.9 m(2) g(-1)) and small size (2-8 nm). The present catalytic process provides sustainability as aqueous medium is used, the reaction proceeded in short reaction times by providing high yields of products and is economical as the catalyst is inexpensive and can be recovered from the reaction mixture. The recovered catalyst can be used for multiple cycles without much loss of its activity. The protocol is green as no chromatographic technique is used, thus eliminating the use of hazardous organic solvents. CoFe2O4 emerged as an efficient, sustainable, stable and recyclable catalyst.