Preparation anchored Pd nanoparticles on glyoxal modified metal- organic framework for Sonogashira coupling reactions

UIO-66-NH2-Gl@Pd nanocatalyst was successfully synthesized during post-synthetic modification (PSM) method and its application was investigated in the Sonogashira coupling reactions. Initially, UIO-66-NH2 was synthesized and identified. This metal organic framework (MOF) was modified with glyoxal, then, palladium nanoparticles (NPs) were supported on the modified framework through PSM. This nanocatalyst was identified via Fourier-transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance ((HNMR)-H-1) spectroscopy, N-2 gas adsorption-desorption, thermogravimetric analyses (TGA), energy dispersive X-ray mapping spectroscopy (EDX-MAP), field emission scanning electron microscopy (FE-SEM), and X-ray diffraction (XRD). (HNMR)-H-1 analysis showed that around 30% of the amine functional groups of nanoporous UIO-66-NH2 were modified with glyoxal. The formation of Pd NPs supported on MOF was confirmed by transmission electron microscopy (TEM) and EDX-MAP. As well, according to the inductive couple plasma atomic emission spectroscopy (ICP), around 2.98 w% of Pd NPs was present in the modified MOF. Eventually, the nanocatalyst provided the excellent catalytic activity in the Sonogashira coupling reaction. Also, the nanocatalyst has the capability to be easily recycled up to 4 times, while its catalytic activity was maintained during the activity. (C) 2019 Published by Elsevier B.V.