Biosynthesis of Fe, Pd, and Fe–Pd bimetallic nanoparticles and their application as recyclable catalysts for [3 + 2] cycloaddition reaction: a comparative approach†
Abstract
The surface adjustment of iron nanoparticles by secondary metals increases the reaction efficiency of bimetallic nanoparticles. This paper reports a green and facile approach for the synthesis of Fe, Pd and Fe–Pd bimetallic nanoparticles using an aqueous bark extract of Ulmus davidiana and their application as magnetically recoverable catalysts for the [3 + 2] cycloaddition of 1,4-naphthoquinones or benzoquinones with β-ketoamides. The surface chemistry of the Fe–Pd bimetallic nanoparticles was determined by X-ray photoelectron spectroscopy. The morphology, size, crystallinity, weight loss, oxidation state, and ferromagnetic behavior of the synthesized nanoparticles were investigated. The bimetallic nanoparticles exhibited strong catalytic activity in high yield for the synthesis of naphtho[1,2-b]furan-3-carboxamides and benzofuran-3-carboxamides compared to their respective monometallic nanoparticles. The nanocatalyst was recovered easily using an external magnetic field and recycled five times without significant loss in activity.