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Development and Application of a Supramolecular Brønsted Acid Catalyst Based on the Noria Macrocycle
Carson Lawrence Hasselbrink1, Josephine Bridget Shirah1, Samantha Renee Sylvain1
1University of Rhode Island, Department of Chemistry, University of Rhode Island, 140 Flagg Rd, Kingston, Rhode Island 02881, United States.
Abstract:
The synthesis of derivatives of the Noria macrocycle and the structurally similar macrocycle, R3, each containing 12 sulfonic acid groups, is reported. Herein, we demonstrate their utility as reusable Brønsted acid catalysts for the Biginelli synthesis of dihydropyrimidinones and the Pechmann synthesis of coumarins. We also demonstrate that the supramolecular structure directs the reagents to interact with the sulfonic acid catalytic sites, thus increasing the catalyst's efficiency compared to other monomeric, macrocyclic, and polymeric sulfonic acid catalysts.
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