Cation-exchange resin as an efficient hetero-geneous catalyst for one-pot three-component synthesis of 2,3-dihydro-4(1H)-quinazolinones

Various mono- and disubstituted 2,3-dihydro-4(1H)-quinazolinones were synthesized efficiently by a one-pot three-component condensation of isatoic anhydride, aromatic aldehydes, and ammonium salts or primary amines using a strong acidic cation-exchange resin as the catalyst in EtOH–H₂O solution. The catalyst is cheap, efficient, stable, and reusable under the reaction conditions. The novel method offers several advantages, such as excellent yields, environmentally friendly reaction media, and simple procedure.