Green Synthesis of Some 2‐Amino‐4 h‐Benzo[H]Chromene Derivatives in the Presence of Bimetallic Nanocomposite Based on Magnetic Mesoporous Silica Nanoparticles at Ambient Conditions

Abstract

AbstractIn this research, some of 2‐amino‐4H‐benzo[h]chromene derivatives were synthesized by multicomponent reaction of 1‐naphthol, benzaldehyde derivatives and malononitrile. The reaction was performed under green conditions using water as the solvent in the presence of heterogeneous nano catalyst containing Co(II) and Cu(II) stabilized on magnetic mesoporous silica nanoparticles/tannic acid (M–MSN/TA/Co(II),Cu(II)) at room temperature. The prepared catalyst showed excellent efficiency and its magnetic properties allow easy separation. The structure and morphology of prepared catalyst was identified using Fourier transform infrared (FT‐IR), X‐ray diffraction (XRD), field emission scanning electron microscopy (FE‐SEM), energy dispersive X‐ray spectroscopy (EDX), elemental mapping, thermogravimetric analysis (TGA) and vibrating‐sample magnetometry (VSM) analysis. All of products were obtained in high to excellent yields (78–94 %) after short reaction times (20–45 min) in optimal conditions and their structures were confirmed using FT‐IR and Proton nuclear magnetic resonance (1H NMR) spectroscopic techniques. This study shows that the M–MSN/TA/Cu(II), Co(II) presents a good catalytic activity, reusability and stability compared to other catalysts.