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An efficient and green catalytic method for friedländer quinoline synthesis using tungstophosphoric acid Included in a polymeric matrix
(Bentham Science Publishers, 2015-05)
A new, efficient and green methodology for obtaining quinolines based on the use of tungstophosphoric acid included in a polymeric matrix of polyacrylamide is proposed (APTPOL60). The methodology involves the formation ...
Kinetic and mechanistic study of the synthesis of ionone isomers from pseudoionone on Brønsted acid solids
(Elsevier Science, 2017-11)
The kinetics of the liquid-phase synthesis of α-, β- and γ-ionones from pseudoionone was studied on Brønsted acid solids. Four silica-supported tungstophosphoric acid catalysts containing different heteropolyacid loadings, ...
Preyssler catalyst-promoted rapid, clean, and efficient condensation reactions for 3H-1,5-benzodiazepine synthesis in solvent-free conditions
(Elsevier, 2013-09-28)
A simple, convenient, and environmentally benign synthesis of 1,5-benzodiazepines is developed by condensing different o-phenylenediamines and 1,3-aryl-1,3-propanodiones. The reaction is catalyzed by a Preyssler ...
Effect of Keggin polyoxometalate on Cu(ii) speciation and its role in the assembly of Cu3(BTC)2 metal-organic framework
(Royal Society of Chemistry, 2011-07)
HKUST-1 is one of the popular metal-organic frameworks (MOFs). The formation of this MOF is significantly accelerated by adding Keggin polyoxometalate anions to the synthesis solution. In this paper the chemistry behind ...
An efficient catalytic route for the preparation of silyl ethers using alumina-supported heteropolyoxometalates
(Elsevier Science, 2010-06)
In the present work the phenol trimethylsilylation with hexamethyldisilazane using molybdophosphovanadates supported on commercial alumina cylinders as catalysts was studied. These catalysts were prepared by incipient ...
Titania hollow spheres modified with tungstophosphoric acid with enhanced visible light absorption for the photodegradation of 4-chlorophenol
(Royal Society of Chemistry, 2017-02)
Titania hollow spheres were synthesized using silica nanospheres as the template. The core was removed using NaOH solution. They were subsequently impregnated with tungstophosphoric acid (TPA) solutions and annealed at two ...
Heterogeneous acid catalysts prepared by immobilization of H3PW12O40 on silica through impregnation and inclusion, applied to the synthesis of 3H-1,5-benzodiazepines
(Elsevier B.V., 2020-04)
Solid acid catalysts were successfully prepared using mesoporous silica (MESOSI) as support and tungstophosphoric acid (KTPA) as active phase, which was incorporated by impregnation (MESOSI#KTPA) and inclusion (MESOSI@KTPA). ...
Obtaining protoanemonin through selective oxidation of Dfructose and 5-(hydroxymethyl) furfural in a self-catalysed reaction
(Wiley Blackwell Publishing, Inc, 2020-09-13)
Although different ways of converting 5- (hydroxymethyl)furfural (1) to various substrates with high value have been sought, few transformations have obtained building blocks that can be very useful in the area of fine ...
Synthesis of ionones on solid Brønsted acid catalysts: Effect of acid site strength on ionone isomer selectivity
(Elsevier Science, 2010-01)
The effect of Brønsted acid site strength on the liquid-phase conversion of pseudoionone to ionone isomers (α-, β- and γ-ionone) was studied on resin Amberlyst 35W, silica-supported heteropolyacid (HPAS) and silica-supported ...