Zr-KIT-6 catalyzed renewable synthesis of N-aryl pyrroles for producing bioactive synthetic compounds

Abstract

The sustainable synthesis of bioactive compounds using biomass-derived platform chemicals is essential to meet future chemical demand. Herein a mild and eco-friendly route is presented for structurally diverse pyrrole derivatives from biomass-derived furan. The furans react with aryl amines to construct N-aryl pyrroles in high yields over a robust Lewis acid Zr-KIT-6. Among the synthesized catalysts of this study, Zr-KIT-6 (20) exhibited excellent performance. The same protocol provides a broad utility to synthesize diverse functional pyrrole derivatives. Mechanistic study over Lewis acid Zr-KIT-6 and Bronsted acid KIT-6-SO3H catalysts indicate that the Lewis acid Zr-KIT-6 follows the direct nucleophilic substitution pathway and Bronsted acid KIT-6-SO3H follows the traditional Pall-Knorr reaction pathway. In addition, the co-catalyst-free straightforward domino process requires mild reaction conditions. The broad synthetic utility of the presented methodology was successfully applied to synthesizing biologically active and pharmaceutically relevant antitubercular and antibacterial active N-aryl pyrrole derivatives from renewable furans.