An Ultrasonic Accelerated Three-Component Condensation By KCC-1: A High Mechanical Stability Silica Nanospheres As A Good Catalyst For Ultrasonic Irradiation

Fibrous nano-silica sphere (KCC-1) has appeared as a good and efficient catalyst for ultrasonic irradiation conditions in chemical reactions. This catalyst has the unique properties such as a fibrous surface morphology, high surface area and high mechanical stability. The results indicated that the KCC-1 nanocatalyst could be used as high-performance catalysts under high temperature and pressure condition in organic reaction under ultrasonic irradiation. Morphology, structure, and composition of the fibrous nano-silica sphere were described by N2 adsorption–desorption analysis, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray powder diffraction (XRD), thermogravimetric analysis (TGA) and Fourier-transform infrared spectroscopy (FT-IR). In this work, we used KCC-1@NH2 nanosilica as a basic catalyst for the preparation of chromenes under ultrasonic irradiation conditions for the first time. The recyclability, nontoxicity and high stability of the catalyst, combined with low reaction times and excellent yields, make the present protocol very useful for the synthesis of the title products under ultrasonic conditions. The produced products were confirmed via 1H NMR, 13C NMR, FT-IR analysis.

Hollow Mesoporous Silica Sphere (HMSS) as a Recyclable Nano-catalyst in an Efficient One-Pot Multicomponent Synthesis of 2-Amino-3-Cyano-4H-Pyran Derivatives

Mesoporous material has a significant role in medicine, health care, environmental monitoring, sensing the hazardous agents, and fighting against viruses and bacteria. Nano-silica sphere is an important member of the mesoporous family that noticeably flourished in biology, health care, and other industrial applications. Efficient one-pot multicomponent syntheses of 2-amino-3-cyano-4H-pyran derivatives were carried out over readily available and simply synthesized recyclable Hollow Mesoporous Silica Sphere (HMSS). Comparable yields were encountered with better efficiency, lower cost, and shorter reaction time. Hence, superior catalytic activity, flexibility, ease of recovery, tuneable hole size, and high surface to volume ratio were the major characteristics of the catalyst which distinguish this protocol from previously reported ones. The catalyst was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) techniques, and nitrogen absorption and desorption (BET) analyses. The results showed that the synthesizing of HMSS catalysts under a mild and green condition in which comparable yields were encountered with better efficiency, lower cost, and shorter reaction with other major economic advantages.

Synthesis of nano-sized tungsten oxide particles encapsulated in a hollow silica sphere and their photocatalytic properties for decomposition of acetic acid using Pt as a co-catalyst

We present a procedure for the synthesis of WO3 nanoparticles encapsulated in a hollow silica sphere, and their unique photocatalytic properties.