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Thiourea dioxide: An efficient and reusable organocatalyst for the rapid one-pot synthesis of pyrano[4, 3-b]pyran derivatives in water
Pyrano[4,3-b]pyran Thiourea dioxide 4-Hydroxy-6-methylpyran-2-one One-pot synthesis
2014/3/11
A series of pyrano[4,3-b]pyran derivatives have been synthesized in excellent yields by the reaction of aromatic aldehydes with malononitrile or cyanoacetate and 4-hydroxy-6-methylpyran-2-one in water...
In situ generation of trityl carbocation (Ph3C+) as a homogeneous organocatalyst for the efficient synthesis of 4, 4’-(arylmethylene)-bis(3-methyl-1-phenyl-1H-pyrazol-5-ol)s
Trityl chloride (Ph3CCl) Trityl carbocation (Ph3C+) 4,4'-(Arylmethylene)-bis(3- methyl-1-phenyl-1H-pyrazol-5-ol) 3-Methyl-1-phenyl-1H-pyrazol-5(4H)-one Solvent-free synthesis
2014/3/11
Trityl chloride (Ph3CCl) efficiently catalyzes the condensation of 3-methyl-1-phenyl-1H-pyrazol- 5(4H)-one and aromatic aldehydes under mild and solvent-free conditions, affording 4,4'- (arylmethylene...
H3PW12O40 catalyzed synthesis of benzoxazine and quinazoline in aqueous media
Heteropoly acid 1,3-Benzoxazine-4-one 2-Substituted-quinazolin-4(3H)-one 2-Substituted-2,3-dihydroquinazolin-4(1H)-one
2014/3/11
A heteropolyacid efficiently catalyzed the cyclocondensation reaction of 2-aminobenzamide and salicylamide with aldehydes and ketones to afford good yields of benzoxazine and quinazoline ring systems ...
Poly(4-vinylpyridinium)hydrogen sulfate: A novel and efficient catalyst for the synthesis of 13-aryl-indeno[1, 2-b]naphtha[1, 2-e]pyran-12(13H)-ones under solvent-free conditions
Poly(4-vinylpyridinium)hydrogen sulfate Indenonaphthopyrans, H-indene-1,3-dione β-Naphthol
2014/3/11
An facile and efficient protocol for the synthesis of 13-aryl-indeno[1,2-b]naphtha[1,2-e]pyran- 12(13H)- ones has been developed that proceeds via the one-pot three-component sequential reaction of an...
![](http://www.firstlight.cn/upload/imgfile/201312/5/201312510393455.jpg)
Silica-bonded N-propylpiperazine sodium n-propionate as recyclable catalyst for synthesis of 4H-pyran derivatives(图)
Silica-bonded n-propylpiperazine sodium n-propionate Heterogeneous solid base catalyst Aldehyde
2013/12/5
Silica-bonded N-propylpiperazine sodium n-propionate (SBPPSP) was found to act as an efficient solid base for the preparation of a series of 4H-benzo[b]pyran derivatives. SBPPSP was used as a recyclab...
![](http://www.firstlight.cn/upload/imgfile/201312/5/2013125102756221.jpg)
Cu(Ⅱ) salen complex catalyzed synthesis of propargylamines by a three-component coupling reaction(图)
Propargylamine Salen Copper Coupling reaction Solvent-free
2013/12/5
A one pot three-component coupling reaction of phenylacetylene, aldehyde, and amine derivatives in the presence of Cu(Ⅱ) Salen complex as an efficient heterogeneous catalyst under solvent-free conditi...
Rice husk ash supported FeCl2·2H2O:A mild and highly efficient heterogeneous catalyst for the synthesis of polysubstituted quinolines by Friedländer heteroannulation(图)
Rice husk ash Supported FeCl2·2H2O, Quinolines 2-Amino benzophenone Solvent-free Friedlä nder heteoannulation
2013/12/5
Rice husk ash was used as a new, green, and cheap adsorbent for FeCl3. Characterization of the obtained reagent showed that rice husk ash supported FeCl2·2H2O was formed. This reagent is efficient at ...
![](http://www.firstlight.cn/upload/imgfile/201310/12/2013101210475500.jpg)
Fe3O4 Nanoparticles as an Efficient and Magnetically Recoverable Catalyst for the Synthesis of 3,4-Dihydropyrimidin-2(1H)-ones under Solvent-Free Conditions(图)
dihydropyrimidinones dihydropyrimidinthiones ferroferric oxide nanoparticle one-pot condensation solvent-free
2013/10/12
The catalytic activity of Fe3O4 nanoparticles (NPs) in a one-pot three component condensation reaction consisting of an aromatic aldehyde, urea or thiourea, and a β-dicarbonyl under solvent-free condi...
![](http://www.firstlight.cn/upload/imgfile/201310/11/2013101122148687.jpg)
Synthesis of Graphene-CdSe Composite by a Simple Hydrothermal Method and Its Photocatalytic Degradation of Organic Dyes(图)
grapheme cadmium selenide organic dye photocatalytic activity
2013/10/11
A graphene-CdSe composite was synthesized by a facile hydrothermal method, and characterized by X-ray diffraction, scanning electron microscopy with energy dispersive X-ray analysis, transmission elec...
![](http://www.firstlight.cn/upload/imgfile/20139/26/2013926103248765.jpg)
Tetrabutylammonium hexatungstate [TBA]2[W6O19]: Novel and reusable heterogeneous catalyst for rapid solvent-free synthesis of polyhydroquinolines via unsymmetrical Hantzsch reaction(图)
Heterogeneous catalysis Polyhydroquinolines Tetrabutylammonium hexatungstate
2013/9/26
A novel, efficient, and environmentally friendly method for the synthesis of polyhydroquinoline derivatives by a one-pot, four-component unsymmetrical Hantzsch condensation of dimedone, aldehydes, eth...
![](http://www.firstlight.cn/upload/imgfile/20139/25/2013925123329546.jpg)
CoFe2O4 nanoparticles:An efficient heterogeneous magnetically separable catalyst for “click” synthesis of arylidene barbituric acid derivatives at room temperature(图)
Magnetically separable catalyst Arylidene barbituric acid derivative Aqueous ethanol Superparamagnetic CoFe2O4 nanoparticle Heterogeneous catalyst
2013/9/25
A coprecipitation method was used to synthesize superparamagnetic CoFe2O4 nanoparticles without using any capping agents/surfactants. The prepared nanoparticles were characterized using Fourier transf...
![](http://www.firstlight.cn/upload/imgfile/20139/25/2013925132938562.jpg)
Magnetically recoverable, nanoscale-supported heteropoly acid catalyst for green synthesis of biologically active compounds in water(图)
Core-shell particle Magnetically recoverable catalyst Heteropoly acid Xanthene Hydroacridine
2013/9/25
12-Tungstophosphoric acid supported on aerosil silica and silica-coated γ-Fe2O3 nanoparticles was prepared and characterized using transmission electron microscopy, scanning electron microscopy, and i...
![](http://www.firstlight.cn/upload/imgfile/20139/25/201392512328140.jpg)
Ionic-liquid-catalyzed green synthesis of coumarin derivatives under solvent-free conditions(图)
Ionic liquid Pechmann reaction Solvent-free synthesis Phloroglucinol Pyrano[2,3-h]coumarin
2013/9/25
Brönsted acidic ionic liquids, namely 2-pyrrolidonium hydrogen sulfate, N-methyl-2-pyrrolidonium hydrogen sulfate, N-methyl-2-pyrrolidonium dihydrogen phosphate, (4-sulfobutyl)tris(4-sulfophenyl)...
![](http://www.firstlight.cn/upload/imgfile/20139/25/2013925211351406.jpg)
Enhanced visible light photocatalytic activity of Ag2S-graphene/TiO2 nanocomposites made by sonochemical synthesis(图)
Silver sulfide Graphene Titanium dioxide UV-Vis absorption spectroscopy Visible light Rhodamine B
2013/9/25
Ag2S-graphene/TiO2 composites were synthesized by a facile sonochemical method. The products were characterized by X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy...
![](http://www.firstlight.cn/upload/imgfile/20139/26/201392696400.jpg)
Synthesis, structural analysis and evaluation of the catalytic activity of a non-symmetric N-(salicylidene)diethylenetriamine complex of copper(II)(图)
Crystal structure Copper(II) complex Non-symmetric Schiff base Catalyst Hydrogen peroxide
2013/9/26
A new copper(II) complex of a non-symmetric Schiff base, [CuII(saldien)(H2O)]+ (1), has been synthesized and characterized by elemental analysis and several other spectroscopic methods (Hsaldien = N-(...