Synthesis, characterization, and application of CoFe2O4@amino‐2‐naphthol‐4‐sulfonic acid as a novel and reusable catalyst for the synthesis of spirochromene derivatives

Abstract

In the present work, 1‐amino‐2‐naphthol‐4‐sulfonic acid immobilized on functionalized CoFe2O4 nanoparticles was successfully synthesized as a new, efficient, and recoverable catalyst and tested for the synthesis of spirochromene derivatives by a simple, green, and inexpensive procedure. This magnetically heterogeneous nanocatalyst was characterized by various techniques such as Fourier transform infrared (FT‐IR), thermal gravimetric analysis (TGA)/derivative thermogravimetric (DTG), X‐ray diffraction (XRD), MAP, transmission electron microscopy (TEM), energy‐dispersive X‐ray spectroscopy (EDS), vibrating sample magnetometer (VSM), Brunauer–Emmett–Teller (BET), and scanning electron microscopy (SEM) analyses. The novel synthesized nanocatalyst can be easily separated and can also be reused several times without appreciable loss in its catalytic activity. Furthermore, in comparison with previous reports, this nanocatalyst showed high thermal stability and acidic properties.