Green synthesis of dicoumarols by Cu (II) immobilized on Fe3O4@SiO2@dimethylglyoxime as a novel and recyclable and nanocatalyst

In last years, catalysts of heterogeneous have been introduced as strategically vital in eco-friendly and various organic conversions due to their unparalleled aspects e.g. excellent catalytic activity, recyclability, low toxicity, and stability.1,2In this work, we synthesized complex of Ni-Dimethylglyoxime immobilized on Fe3O4 of covered with SiO2 by a post-grafting way and utilized as a novel4, thermally stable, recoverable, and efficient for clean synthesis of dicoumarols3 through the interaction of various aldehydes5 with 4- hydroxycoumarin6 in excellent yields and higher rate (Figure 1). Fe3O4@SiO2-silylcyclopropyl-dimethylglyoxime-Ni superparamagnetic nanoparticles (MNPs) were investigated by FT-IR, SEM, EDS, XRD, VSM, and BET technique. This nanocatalyst could be easily regained via the utilization of a magnet and reused for subsequent reactions for at least 7 times without any remarkable change and decrease in catalytic activity.7

Keywords:

Dimethylglyoxime , Magnetic nanoparticles , Core-shell , Dicoumarols