Green synthesis of Cu nanoparticles on the surface of porphyrin-functionalized metal–organic framework using Aloe vera extract (TMU-17-NH-Por@Cu) as a unique heterogeneous catalyst for Biginelli reaction

Abstract

In this research, a hematoporphyrin-functionalized metal–organic framework is introduced as a new and unique platform for stabilization of Cu nanoparticles. For the first time, hematoporphyrin (Por) has been incorporated as a ligand onto TMU-17-NH₂ to create a stable support for the deposition of Cu nanoparticles to design a highly active, stable, and reusable catalyst for the Biginelli condensation reaction. The synthesis and stabilization of Cu nanoparticles on the surface of TMU-17-NH-Por were performed using Aloe vera extract as a reducing and stabilizing agent. In this procedure, neither chemical reducing agent nor any gaseous hydrogen is used for the synthesis of the copper nanoparticles. The Biginelli reaction is catalyzed with TMU-17-NH-Por@Cu under mild and green conditions at atmospheric pressure. The role of the Por ligand that is based on four pyrrole-like moieties with abundant electron-rich atoms with the decrease in Cu mol% and the increase in stability was notable.