Guanine base stabilized on the magnetic nanoparticles as recyclable catalyst “on water” for the synthesis of spirooxindole derivatives, By Khodabakhsh Niknam

Research

Title	Guanine base stabilized on the magnetic nanoparticles as recyclable catalyst “on water” for the synthesis of spirooxindole derivatives
Type	Article
Keywords	Guanine; Bis-spirooxindoles; Heterogeneous base catalyst; Magnetic nanoparticles; “On water”.
Journal	JOURNAL OF ORGANOMETALLIC CHEMISTRY
DOI	10.1016/j.jorganchem.2021.121912
Researchers	Dariush Saberi (First researcher) , Mohammad Bashkar (Second researcher) , Arash Rezaei (Third researcher) , Zohre Azizi (Fourth researcher) , Khodabakhsh Niknam (Fifth researcher)

Abstract

Guanine stabilized on the surface of silica-modified magnetic nanoparticles, by the propyl group as a linker, (Fe3O4@SiO2-n-(propyl)-guanine), was prepared, identified and used as a recyclable base in the synthesis of novel spirooxindole compounds and highly substituted dihydro-2-oxopyrroles in aqueous media. Fe3O4@SiO2-n-(propyl)-guanine was characterized via some spectroscopic and microscopic techniques such as Infrared spectroscopy (IR), X-ray diffraction spectroscopy (XRD), Energy dispersive X-ray spectroscopy (EDX), Vibrating sample magnetometry (VSM), Scanning electron microscopy (SEM), High resolution transmission electron microscopy (HR-TEM), Thermo-gravimetric analysis (TGA) and NMR-detected hydrogen/deuterium (H/D) exchange technique. The synthesized nanocomposite was employed as a new base catalyst for the synthesis of some novel spirooxindole compounds and highly substituted dihydro-2-oxopyrroles in aqueous media with good to excellent yields. This heterogeneous base catalyst could be recycled and reused up to ten times without appreciable loss of activity.