new, stable and reusable magnetic fe3o4/peg@cptms-thioaminophenol@ni nanocatalyst for the synthesis of dispiro-cyclopropanes’s meldrum’s acid

Magnetic fe3o4/peg@cptms-thioaminophenol@ni nanocatalyst as a heterogeneous, stable and reusable nanocatalyst was formed. this nanocatalyst was characterized by ft-ir, xrd, tga, icp, sem, eds and vsm techniques and was used for six times without decreasing activity. this nanocatalyst was used successfully for the synthesis of 3,3,10,10-tetramethyl-13-aryl(alkyl)-2,4,9,11-tetraoxadispiro[5.0.57.16]tridecane-1,5,8,12-tetraones (dispiro-cyclopropane’s based on meldrum’s acid) by the reaction of various aldehydes and meldrum’s acid in the presence of triethylamine and cyanogen bromide in excellent yield.