Perfluoroalkyl acids sources

Valsecchi, S. Polesello, S., The search of sources of perfluoroalkyl acids (PFAAs) in Northern Italian waters. In SETAC 19th annual meeting, Goleborg, 2009 Poster presentation abstract book, p. 129... 

Aryl-A3-iodanes bearing an electron-deficient alkyl ligand such as aryl(sul-fonylmethyl)-A3-iodanes (Section 3.2.7) and aryl(perfluoroalkyl)-A3-iodanes are relatively stable. A series of (perfluoroalkyl)phenyl-A3-iodanes 96 were synthesized in good yields by treating bis(trifluoroacetoxy)-A3-iodanes with benzene in the presence of triflic acid [47]. The AModanes 96 transfer the perfluoroalkyl groups to a variety of nucleophiles with reductive elimination of iodobenzene. The nucleophiles involve Grignard reagents, alkyllithiums, enolate anions, alkenes, alkynes, trimethylsilyl enol ethers, arenes, phenols, and thiols. In these reactions, the AModane 96 serves as a source of the perfluoroalkyl cation and, in... 

Perfluoroalkylmercury compounds have been prepared by reaction of perfluoroalkyl halides with cadmium amalgam or by reaction of fluoroalkenes with mercury(II) fluoride. Due to the high thermal stability of perfluoroalkylmercury compounds, they can be sublimed from concentrated sulfuric acid without decomposition and are of limited synthetic utility. These reagents have found use as difluorocarbene sources and do react with elemental sulfur at elevated temperatures to afford thioacid fluorides, di- and polysulfides, and thioketones. ... 

The development of new polymeric materials for polymer electrolyte fuel cell is one of the most active research areas, aiming at the new energy sources for electric cars and other devices. The mainstream of the material research for fuel cell is perfluoroalkyl sulfonic acid membranes such as Nafion, Acipex, and Flemion. The most well-known one is Nafion of Du Pont, which is derived from copolymers of tetrafluoro-ethylene and perfluorovinyl ether terminated by a sulfonic acid group.Protons, when dissociated from the sulfonic acid groups in aqueous environment, become mobile and the membrane becomes a proton conducting electrolyte membrane. 

A synthesis of partially-fluorinated cyclopentanecarboxylic acids based on the cyclization of hepta-1,6-dienes by perfluoroalkyl radicals generated from iodides has been developed (e.g. see Scheme 2) and 1 1 perfluoroalkyl iodide-olefin adducts of the type RpCHg-CHI-CHj CHXY [Rp = perfluoroalkyl X,Y = COgH, CX)2R, CX)R, or CN (R = alkyl)] have proved to be convenient sources of perfluoroalkylated cyclopropanes (e.g. see Scheme 3). F N.m.r. analysis of the 3,3,3-trifluoro-l-iodopropene and 3,3,4,4,4-pentafluoro-l-iodobutene prepared by u.v.-induced addition of trifluoroiodomethane and pentafluoroiodoethane, respectively, across the multiple bond in acetylene has revealed that the irons adducts predominate (CFg-CH CHI, cwr/roras = 1 6.7 CgFs-CHiCHI, cisUrans = -Si). cis-Addition across acetylene is much more important in the case of heptafluoro-2-iodopropane, the ratio of c/j- /ra s-(CFs)2CF-CH CHI being 1 1.78. ... 

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