Hybrid magnetic Irish moss/Fe3O4 as a nano-biocatalyst for synthesis of imidazopyrimidine derivatives

摘要

Irish moss (IM), derived from the Chondrus crispus is a family of sulphated polysaccharide that are extracted from certain kinds of algae (red edible seaweeds). In this study, new magnetically separable, recoverable Fe _(3) O _(4) nanoparticles were synthesized in the presence of natural Irish moss (IM) to afford Fe _(3) O _(4) @IM. FT-IR analysis, scanning electron microscopy (SEM), transmission electron microscopy (TEM), VSM analysis, Energy-Dispersive X-ray Spectroscopy (EDX) and X-ray diffraction (XRD) were combined for the characterization of the Fe _(3) O _(4) @IM nanocomposite. Afterward, the first catalytic report of Fe _(3) O _(4) @IM with no post-modification was achieved by studying its catalytic activity in the synthesis of imidazopyrimidine derivatives via a three-component reaction of 2-aminobenzimidazole, aldehyde, and C–H acidic compounds under reflux in ethanol. ~(1) H nuclear overhauser effect (NOE) experiments have been used to ascertain the regioselectivity of addition and condensation reactions. Based on this study, Fe _(3) O _(4) @IM is an efficient, magnetically separable, recyclable, and green catalyst.