Showing papers by "Murlidhar S. Shingare published in 2017"

Silica nanosphere-graphene oxide (SiO2-GO) hybrid catalyzed facile synthesis of functionalized quinoxaline derivatives

Abstract: Herein, fabrication of spherical SiO2 nanoparticles (5 ± 0.2 nm) with uniform size is followed by their homogeneous distribution on graphene oxide (SiO2–GO) by using a simple in situ one-step method. These as synthesized catalytic materials are further characterized by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), and others. This spectroscopic characterization demonstrated that GO acted as a good supportive substrate for controlling the size and activity of SiO2 nanospheres with their cooperation towards catalytic reactions. The optimized hybrid exhibited high catalytic activity for the synthesis of functionalized quinoxalines. Significantly, the as-synthesised SiO2–GO nanohybrid catalysed reaction, for the first time, was shown to be highly efficient in mild conditions (i.e., room temperature, air) with excellent product yield (92 %) and good recyclability (up to four cycles) at room temperature.

Visible light motivated synthesis of polyhydroquinoline derivatives using CdS nanowires

Abstract: In this article, we report the synthesis of one-dimensional cadmium sulphide nanowires (CdS NWs) by chemical synthesis approach. These as-synthesized materials were characterized by ultraviolet–visible spectroscopy, X-ray diffraction, scanning electron microscopy with energy dispersive spectroscopy, and transmission electron microscopy analysis. These nanowires have an average diameter of ~20 nm and length up to several micrometres. CdS NWs are highly stability and are found to be a very efficient recyclable/reusable (minimum four times without any significant loss) photocatalyst for polyhydroquinoline synthesis under visible light (Halogen lamp, 70 W) at room temperature. This system offers a mild, efficient, and highly economical alternative to the existing protocols in its catalytic activity under visible light irradiation (λ ≥ 420 nm). These findings will open up new opportunities for developing low-cost efficient photocatalyst synthesis of value added intermediates.