Plant-Mediated Green Synthesis of Zinc Oxide Nanoparticles and Their Catalytic Application in Synthesis of Substituted Hydroxy Thiazole Derivatives

A sustainable green synthesis of zinc oxide nanoparticles (ZnO NPs) is presented using Dolichandrone falcata leaf extract as reducing, capping and stabilizing agent. The phytochemical screening of the leaf extract showed the presence of flavonoids, phenolics, steroids, triterpenoids, and saponins which help in the formation and stabilization of the nanoparticles. The catalytic activity of the Df–ZnO NPs was tested for the synthesis of substituted hydroxy thiazole derivatives under mild and green conditions. The reactions were performed in ethanol at 80 °C for 1 h and gave the desired products in good yields. The structures of the products were confirmed by FTIR, 1H NMR and 13C NMR spectroscopy. The results indicate that Df–ZnO NPs are efficient heterogeneous catalysts for the preparation of substituted hydroxy thiazoles providing a green and recyclable substitute to the conventional catalysts. This work highlights the potential of plant mediated ZnO nanoparticles as sustainable catalytic materials for synthesis of organic compounds.