Preparation, characterization and catalytic application of Zn‐based metal–organic framework catalyst for synthesis of 3,3‐(arylmethylene)bis‐1H‐indole derivatives

Abstract

BACKGROUND A mesoporous zinc‐based pyridine‐2,5‐dicarboxylate metal–organic framework (Zn‐based MOF) catalyst was prepared by a solvothermal method. The catalytic potency of Zn‐based MOF for the one‐pot synthesis of 3,3‐(arylmethylene)bis‐1H‐indole derivatives was investigated. RESULTS Various analytical techniques were used to characterize the physicochemical structure of Zn‐based MOF catalyst, including powder X‐ray diffraction, thermogravimetric analysis, scanning electron microscopy–energy‐dispersive X‐ray analysis, Fourier transform infrared spectroscopy and Brunauer–Emmett–Teller surface area analysis. Zn‐based MOF was then employed as a catalyst for the catalytic one‐pot transfer synthesis of 3,3‐(arylmethylene)bis‐1H‐indole derivatives. Optimizations of Zn‐based MOF catalyst in terms of effect of solvent and reaction time were investigated. CONCLUSIONS Zn‐based MOF catalyst was synthesized by solvothermal treatment, characterized and used as a Lewis acid catalyst for the synthesis of biologically active 3,3′‐(arymethylene)bis‐1H‐indole derivatives. The catalyst offers notable benefits such as reusability of catalytic character, easy separation, nontoxicity, large pore size and providing excellent yield of 3,3′‐phenylmethylene‐1H‐indole derivatives. Zn‐based MOF was confirmed as containing tetragonal phase with large pore diameter, morphology looking like a spherical core and exhibiting no significance loss of catalytic performance when used in organic synthesis for three to four reaction runs. Thereby Zn‐based MOF was evidenced as showing excellent catalytic activity. © 2022 Society of Chemical Industry (SCI).