A Green and Sustainable Access to 2,3-Dihydroquinazolin-4(1H)-ones Using Nanosized Heterogeneous Metal/Metal Sulfide@Carbon Catalyst

A green sustainable one-pot multicomponent condensation of aldehydes, isatoic anhydride, and ammonium acetate in refluxing ethanol has been developed for the synthesis of 2,3-dihydroquinazolin-4(1H)-ones using copper, zinc sulfide, or nickel sulfide-loaded carbon-based heterogeneous catalysts prepared from metal salt-loaded sulfonate-functionalized styrene–divinylbenzene copolymers. The developed protocol is efficient, convenient, and superior to the existing methods for the synthesis of dihydroquinazolin-4(1H)-ones. High yields, environmentally benign conditions, simple work-up, and catalyst reusability without a significant loss in catalytic efficiency are the main advantages of this protocol.