52447-22-0Relevant articles and documents
Preparation method of fluorine-containing carboxylic acid
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Paragraph 0046, (2020/07/12)
The invention discloses a preparation method of fluorine-containing carboxylic acid. The method comprises the following steps: reacting fluorine-containing carboxylate used as a raw material with an acylating chlorination reagent to obtain a corresponding mixture of fluorine-containing acyl chloride and fluorine-containing anhydride, and hydrolyzing and drying the mixture of fluorine-containing acyl chloride and fluorine-containing anhydride to obtain high-purity fluorine-containing carboxylic acid. The method provided by the invention is suitable for post-treatment of fluorine-containing carboxylic acid prepared by a fluorine-containing olefin (monoolefine, diene, cycloolefin and the like) oxidation method, replaces the traditional strong acid acidification and ether continuous extractionprocess, and is simpler, more convenient and more applicable; and the method can also be used for recovering and purifying a fluorine-containing carboxylate emulsifier. The purity of the fluorine-containing carboxylic acid prepared by the method can reach 98% or above.
Multiple pathways in cyclodextrin-catalyzed hydrolysis of perfluoroalkylamides
Granados, Alejandro,De Rossi, Rita H.
, p. 3690 - 3696 (2007/10/02)
The hydrolysis of p-nitroanilide of perfluoroalkanoic acids, CF3(CF2)nCO-, with n = 1, 2, 3, 5, 6, and 7, 1a-f, was studied in the presence of β-cyclodextrin (CD). All reactions were catalyzed by CD through the formation of a 1:1 and 1:2 inclusion complexes. The association equilibrium constants for the 1:1 complexes were dependent on the number of carbons of the fluoroalkyl chain, whereas those of the 1:2 complexes were almost independent. These results indicate that, in the former case, the perfluoroalkyl chain is included, while in the latter, the CD unit encloses the aryl ring. For compounds 1a,b both complexes were more reactive than the substrate itself. The ratio of the reaction of complexed to uncomplexed substrate had its highest value for 1a in the case of the 1:1 complex, and for 1b, the 1:2 complex. This is attributed to the geometry of the complexes. Although compounds 1c-e reacted at the same rates in the free or 1:1 complexed form, CD accelerated the reactions because of an increase of the pKa of the substrate, which results in a higher concentration of the neutral reactive substrate at the same pH. Compound 1f formed aggregates even at 10-6 M concentration, and CD-induced deaggregation resulted in catalysis of the reaction.
PYROLYTIC REACTIONS OF PERFLUORINATED CARBOXYLIC ACID HALIDES
Podsevalov, P. V.,Bil'dinov, I. K.,Rychkov, M. L.,Deev, L. E.,Igumnov, S. M.
, p. 1269 - 1273 (2007/10/02)
Unlike other acyl halides, perfluoroacyl fluorides only enter into reaction with polar reagents.Perfluoroacyl fluorides, perfluoroacyl bromides, and perfluoroacyl iodides are smoothly decarbonylated at active carbon at elevated temperatures.In the absence of the active carbon the perfluoroacyl fluorides react with halogens, polyhalogenoalkanes, and iodoperfluoroalkanes with the formation of the corresponding halogenoperfluoroalkanes or their mixtures with perfluoroacyl halides; the low yields of the iodoperfluoroalkanes in the reaction of perfluoroacyl fluorides withiodine are explained by their ability to act themselves as reagents in these processes.The catalytic properties of active carbon are due to its ability to transfer electrons to the molecules of the adsorbed reagent and to hold the reaction particles on the surface; graphite and nickel also have specific catalytic activity.
