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Fe3O4@MCM‐41@Zr‐MNPs modified with piperazine is easily prepared and characterized using Fourier transform infrared spectroscopy (FT‐IR), X‐ray powder diffraction (XRD), N2 adsorption–desorption, Transmission electron microscopy (TEM), Energy‐dispersive X‐ray (EDX), Vibrating sample magnetometry (VSM) and Thermogravimetric analysis (TGA) techniques. The characterization results showed that Zr highly dispersed in the tetrahedral environment of silica framework and piperazine is successfully attached to the surface of the nanocatalyst in connection with zirconium. The prepared nanosized reagent (10–30 nm), shows excellent catalytic activity in the synthesis of tetrahydro‐4H‐chromene and pyrano[2,3‐d]pyrimidinone derivatives. All reactions are performed under mild and completely heterogeneous reactions conditions in high yields during short reaction times. On the other hand and due to its superparamagnetic nature the catalyst can be easily separated by the application of an external magnetic field and reused for several times.

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The present article reports the synthesis of a new magnetic mesoporous nanocomposite with core-shell structure, formulated as Fe 3 O 4 @MCM-41@ZrCl 2 . The prepared reagent was successfully characterized using different types of methods. The combination of unique properties of MCM-41 as an inimitable mesoporous compound, satisfying magnetic nature of the Fe 3 O 4 magnetic nanoparticles and substantial catalytical applications of zirconium, caused the favorable efficiency of the intended nanocomposite in the synthesis of 1-(benzothiazolylamino)phenylmethyl-2-naphthols via a multicomponent condensation reaction of 2-aminobenzothiazole, 2-naphthol, and aromatic aldehydes in absence of solvent in good to high yields (70-90%). Green conditions of the reactions, easy separation, practicability, product purity, reusability of the catalyst, affordability, and environmentally profits are the considerable advantages of this protocol.