writer：Z. M. Sun, F. Y. Liu, X. Y. Yang, XP Huang, MM Zhang, GM. Bian, YL Qi, XL Yang*, WQ Zhangh
keywords：Cascade reaction, Acid/base bifunctional catalyst, Physically mixed bifunctional catalyst
source：期刊
specific source：New J Chem., DOI: 10.1039/D0NJ01357A
Issue time：2020年

In this article, the acid/base bi-functional polymeric materials were prepared by a physically mixed porous poly(divinylbenzene-co-4-vinylbenzenesulfonic acid) (P(DVB-VBS)) with sulfonic acid groups and poly(divinylbenzene-co-4-vinylbenzyl amine) (P(DVB-VBA)) with amino groups, which were synthesized by a solvothermal polymerization of crosslinker DVB with either phenyl 4-vinylbenzenesulfonate (PVBS) or 4-vinylbenzyl amine hydrochloride (VBAH) functional monomers together with subsequent hydrolization or alkaline treatment. The bi-functional polymeric materials were utilized as a synergistic catalytic system for one-pot cascade reactions including deacetalization-Henry condensation reaction,deacetalization-Knoevenagel condensation reaction and the transformation of 3,4-dihydropyran derivatives to α-ester cyclohexenones compounds. The crosslinked polymeric frameworks effectively isolated sulfonic acid and primary amine groups to ensure their roles as both acid and base catalyst simultaneously in one-pot system. The hierarchical porosity of physically mixed acid/base co-catalyst system provided the possibility for the multi-step transformation of more complex

substrates.