N-Arylation of indole and aniline by a green synthesized CuO nanoparticles mediated by Thymbra spicata leaves extract as a recyclable and heterogeneous nanocatalyst

Abstract

In a biological procedure where the aqueous leaves extract of Thymbra spicata was utilized as a reducing and capping agent, copper oxide (CuO) nanoparticles (NPs) were synthesized. These CuO NPs were characterized via Fourier transformed infrared spectroscopy (FT-IR), X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDS), wavelength-dispersive X-ray spectroscopy (WDX), and UV–visible spectroscopy. The as prepared nanoparticles have been employed as an appropriate nanocatalyst for ligand-free N-arylation of indole and aniline via Ullmann-type CN coupling reactions. Adequate to outstanding quantities of the N-arylated products were synthesized and the nanocatalyst was retrievable and reusable seven times without noticeable decrease in catalytic performance.