Efficient synthesis of mono- and disubstituted 2,3-dihydroquinazolin-4(1H)-ones using copper benzenesulfonate as a reusable catalyst in aqueous solution

Copper benzenesulfonate was found to be an effective catalyst for one-pot three-component cyclocondensation of isatoic anhydride, aromatic aldehydes, and ammonium salts or primary amines in aqueous solution to afford the corresponding mono- and disubstituted 2,3-dihydroquinazolin-4(1H)-ones in good yields. The catalyst is reusable and could be recycled for several times without distinct decrease in its efficiency.