Sobhan Rezayati - Islamic Azad University
Zahra Abbasi - Chemistry Department, College of Science Shahid Chamran University, Ahvaz, Iran
Eshagh Rezaee Nezhad - Department of Chemistry, Payame Noor University, PO BOX ۱۹۳۹۵-۴۶۹۷ Tehran, Iran
Rahimeh Hajinasiri - Chemistry Department, Qaemshahr Branch, Islamic Azad University, P.O. Box ۱۶۳, Qaemshahr, Iran
Shahin Soleymani Chalanchi - ۱Department of Chemistry, Payame Noor University, PO BOX ۱۹۳۹۵-۴۶۹۷ Tehran, Iran

A simple and facile method for the preparation ofFe۲+ supported on hydroxyapatite-core-shell-γ-Fe۲O۳ nanoparticles (γ-Fe۲O۳@HAp-Fe۲+ NPs) as an environmentally friendly and recyclable green catalyst is described and used for the one-pot synthesis of benzimidazoles and benzoxazole derivatives via reactions between aromatic aldehydes and ortho‐phenylenediamine or ortho‐aminophenol in aqueous media conditions at room temperature. This green method offers significant advantages in terms of its simplicity, very low loading of catalyst, high catalytic efficiency, good to excellent product yields, short reaction time, simple experimental and work-up procedure. Also, after the reaction, γ-Fe۲O۳@HAp-Fe۲+ NPs can be easily recovered and reused for at least ten runs. This magnetic nanoparticle was characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscope (SEM) and vibrating sample magnetometry (VSM) spectra.

γ-Fe۲O۳@HAp-Fe۲+ NPs, Lewis acid, Magnetic nanoparticle, Benzimidazole, Benzoxazole