Zno Nanoparticles Embedded On A Reduced Graphene Oxide Nanosheet (Zno-Nps@R-Go) As A Proficient Heterogeneous Catalyst For A One-Pot A(3)-Coupling Reaction

This study reports a simple and facile route for the synthesis of ZnO nanoparticles (ZnO-NPs) decorated on reduced graphene oxide nanosheet (ZnO-NPs@r-GO) as a heterogeneous catalyst and tested over multicomponent one-pot A(3)-coupling reaction. The reduction of graphene oxide with the anchoring of ZnO-NPs on the r-GO nanosheet was observed through the X-ray diffraction patterns, Raman, FTIR, and XPS results of the ZnO-NPs@r-GO sample. ZnO-NPs (average particle size of 3.4 +/- 1.5 nm) with uniform size distribution over r-GO nanosheet were substantiated through HRTEM analysis. Impressively, ZnO-NPs@r-GO significantly used for A(3)-coupling reaction with different aromatic aldehydes, active methylene compounds, and urea and under the optimized reaction conditions gave exceptional activity to produce synthetically valuable 3,4-dihydropyrimidinones products (possessing diverse therapeutic and pharmacological properties) i. e. 97 % isolated yield of the product. In addition, excellent reusability up to 4 repeated cycles are the key advantages of the present catalyst used for this multicomponent A(3)-coupling reaction.