Cu2O-Decorated Marigold Hollow Alumina Microsphere Nanoparticles as a Robust and Efficient Catalyst for the Synthesis of Isoquinolones

Abstract

The design of a heterogeneous catalyst involving plentifully accessible transition metal-based nanoparticles for the sustainable synthesis of valuable N-heterocycles has attracted much attention in recent years. The isoquinolone moiety is one of the privileged pharmacophores found in various natural products and drug molecules, so development of its synthetic methodology has always been in demand. Herein, we report a novel Cu2O-decorated marigold hollow alumina microsphere nanocatalytic system for the synthesis of isoquinolones using 2-bromobenzonitriles and ketones under neat condition. The prepared nanocatalyst was well characterized by scanning electron microscopy, high-resolution transmission electron microscopy, powder X-ray diffraction, energy-dispersive X-ray analysis, X-ray photoelectron spectroscopy, and Brunauer–Emmett–Teller techniques. The present method is facile and showed better green chemistry metrics such as low E-factor, high reaction mass efficiency, and high turnover number and can be reused for five cycles without any loss in its catalytic activity.