Halogenated macroporous sulfonic resins as efficient catalysts for the Biginelli reaction
•Halogenated macroporous sulfonic resins were synthesized from Amberlyst 15.•Hydrophobicity of the halogenated resins was improved.•The halogenated resins possessed an improved thermal stability.•A-15-Br containing 31.27% bromine exhibited the best catalytic activity and excellent recyclability.
A series of halogenated macroporous sulfonic resins A-15-Cl, A-15-Br and A-15-I were synthesized from the precursor Amberlyst 15 by a typical halogenation reaction, and they were evaluated for the catalytic activities of the halogenated macroporous sulfonic resins via the Biginelli reaction in detail. These modified resins possessed a larger contact angle of water droplet than the precursor and a significantly improved thermal stability, which contributed to their higher catalytic activity. In particular, the resin A-15-Br containing 31.27% bromine exhibited the best catalytic activity and excellent recyclability.
Graphical abstractHalogenated macroporous sulfonic resins were synthesized and employed as the catalysts for the Biginelli reaction.Figure optionsDownload full-size imageDownload as PowerPoint slide
Journal: Catalysis Communications - Volume 77, 5 March 2016, Pages 18–21