Greener approach for synthesis of monodispersed palladium nanoparticles using aqueous extract of green tea and their catalytic activity for the Suzuki-Miyaura coupling reaction and the reduction of nitroarenes

A facile and green route for the synthesis of palladium nanoparticles (NPs) was developed utilizing non-toxic and renewable natural green tea extract as the reducing, stabilizing and capping agent. The as-prepared Pd-NPs@G. Tea extract was characterized using UV-visible spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, field-emission scanning electron microscopy, transmission electron microscopy and energy-dispersive X-ray spectroscopy. The Pd-NPs@G. Tea extract could be used as an efficient and heterogeneous catalyst for Suzuki coupling reactions between phenylboronic acid and a range of aryl halides containing iodo, bromo and chloro moieties, and also for the reduction of nitroarenes using sodium borohydride in an environmentally friendly medium. Excellent yields of products were obtained with a wide range of substrates and the catalyst was recycled multiple times without any significant loss of its catalytic activity.