Ultrasonication‐assisted Synthesis of α, β‐Unsaturated Compounds Catalyzed by Amino‐functionalized FDU‐12 Catalyst

Abstract

Amino-group functionalized FDU-12 material (FDU-12-NH 2 ) was utilized as an efficient and recyclable catalyst for the Knoevenagel condensation to afford α, β-unsaturated compounds. The catalysts were characterized by nitrogen adsorption, X-ray diffraction, Fourier transform infrared spectrophotometer, scanning electron microscopy, transmission electron microscopy and thermogravimetric analysis, which showed that FDU-12-NH 2 was successfully prepared using the post-synthesis-grafting method. Compared with the magnetic stirring method, the ultrasound-assisted method could improve the Knoevenagel reaction significantly in this work. In addition, the catalyst exhibited the highest catalytic activity in the mixed solvent of ethanol and water with volume ratio of 3 : 1 due to the solvent effect. Various substrates could convert to their desired products with high yields in short time; what's more, it could be used for four times without significant decrease of the activity. This work reveals that FDU-12-NH 2 is a promising heterogeneous catalyst for the synthesis of α, β-unsaturated compounds.

WOx‐Modified Ni Catalyst Supported on Mesoporous Silica with Extra‐Large Mesopores for CO Methanation

“…Figure shows N 2 adsorption–desorption isotherms and pore (cage and window) size distribution curves of FDU‐12, 10NF‐H 2 O, 10N1WF‐H 2 O, 10NF‐EC, and 10N1WF‐EC. All isotherms are of type IV with broad H2 hysteresis loops that are the characteristic of mesoporous materials with cage‐type structures . Meanwhile, their shapes of isotherms and hysteresis loops are still similar to those of FDU‐12, signifying that the addition of Ni, W species, and carbon species does not damage the mesoporous structure of FUD‐12.…”

Sodium Tungstate Supported on a Three‐dimensional and Networked SBA‐15 for Knoevenagel Reaction

“…At the same time, the pure phase Na 2 WO 4 was also analyzed as a reference. For 3D ‐SBA‐15, there are three peaks at 1097, 802 and 456 cm −1 , which are attributed to stretching and bending vibration of Si–O–Si bonds . For mST/ 3D ‐SBA‐15, the strong absorption band at 828 cm −1 originates from the O–W–O stretches of WO 4 tetrahedron .…”

“…Sodium tungstate can be a homogeneous catalyst for Knoevenagel reaction, whose reusability test is complicated and needs large amounts of solvents. Therefore, design of sodium tungstate based heterogeneous catalysts for Knoevenagel condensation could be as effective and attractive strategy . Ordered mesoporous materials with large surface areas and controlled specific morphologies have drawn great attention in catalysis as well as in materials science .…”

“…Ordered mesoporous materials with large surface areas and controlled specific morphologies have drawn great attention in catalysis as well as in materials science . Catalysts with silica‐based SBA‐15, MCM‐41, KIT‐6 or FDU‐12 have been widely reported. Among them, extensive investigation on synthesis of mesoporous SBA‐15 materials with controlled specific morphologies at both the micro‐ and macro‐scale levels has been conducted for the application in drug delivery, photonics, electronics, and magnetic separation .…”

Three‐Component Mannich Reaction Catalyzed by Mesostructured Cellular Foam Silica Immobilized H3PW12O40

“…It has been utilized in many fields such as adsorption, separation and catalysis due to its unique pore characteristics of high surface area and large pore volume. Following our research studies on Mannich reaction and catalytic, especially for the demand green synthesis. The immobilization of H 3 PW 12 O 40 (free of crystal water) on MCF can be employed to derive a novel heterogeneous catalyst system that possesses a relatively high surface area to maximize catalyst loading and activity.…”