Core‐shell structured magnetite silica‐supported hexatungstate: A novel and powerful nanocatalyst for the synthesis of biologically active pyrazole derivatives

Abstract

This article describes the synthesis of a novel core-shell structured magnetic silica-supported hexatungstate (Fe 3 O 4 @SiO 2 -NH 3 [W 6 O 19 ]) nanocatalyst through immobilization of hexatungstate on amine-modified magnetic silica nanoparticles. The physicochemical properties of Fe 3 O 4 @SiO 2 -NH 3 [W 6 O 19 ] were investigated by using Fourier transform infrared (FT-IR) spectroscopy, powder X-ray diffraction, vibrating sample magnetometer, wide-angle PXRD, scanning electron microscopy, transmission electron microscopy, and energydispersive X-ray spectroscopy analyses. The Fe 3 O 4 @SiO 2 -NH 3 [W 6 O 19 ] nanocatalyst was used as a powerful and heterogeneous catalyst in the synthesis of pyrazole derivatives. This novel catalyst was reused at least seven times without loss of its activity.

Síntesis de nanocatalizadores basados en nanopartículas de óxido de hierro: una revisión bibliométrica

“…En cambio, los óxidos metálicos ofrecen altas estabilidades térmicas y químicas combinadas con una estructura porosa bien definida y áreas superficiales altas. Entre los óxidos más utilizados se encuentran el óxido de silicio o sílice [55], alúmina [56], óxido de titanio [57], óxido de cerio [58], la circonia, y óxidos de hierro como la magnetita [59].…”

Magnetic Nanoparticles‐Supported Synthesis of Pyrazole Scaffolds: A Review

“…The group of Shaker [113] demonstrated a newly developed nanocatalyst with a core‐shell structure denoted as Fe 3 O 4 @SiO 2 ‐NH 3 [W 6 O 19 ] (Scheme 49). The structure and properties of nano catalyst were examined through the application of various analytical techniques, including FT‐IR, powder X‐ray diffraction and vibrating sample magnetometer etc.…”