Sulfonic acid–functionalized Wang resin (Wang-OSO₃H) as polymeric acidic catalyst for the ecofriendly multicomponent synthesis of polyhydroquinolines via Hantzsch condensation

<p>An efficient and green approach has been developed for the synthesis of polyhydroquinoline derivatives via Hantzsch condensation reaction directly from corresponding substituted aromatic and aliphatic aldehydes, β-keto compounds, active methylene compounds, and ammonium chloride using recyclable polymer-supported sulfonic acid catalyst under aqueous conditions. Environmental acceptability, operational simplicity, low cost, excellent functional group compatibility, and high yields are the important features of this protocol.</p