Novel nanomagnetic material with dimethylamino tag: a selective and recyclable catalyst for the reaction of malononitrile, aryl aldehydes and dimedone

A novel nanomagnetic material with a dimethylamino tag namely nano-Fe3O4@SiO2@R-NMe2 ([NFSRN]) was produced, and characterized by EDS, FT-IR, VSM, FE-SEM, XRD and TGA analyses. Then, it was applied as a highly effective and magnetically recyclable catalyst for the one-pot multi-component reaction of malononitrile, arylaldehydes and dimedone. Interestingly, in most entries, among the possible products which can be produced from the reactants, only 2-amino-tetrahydrobenzo[b]pyrans were obtained in high yields and relatively short times, and no other product was obtained.