Fluonnated free radicals

Carboxylic acids react with xenon difluoride to produce unstable xenon esters The esters decarboxylate to produce free radical intermediates, which undergo fluonnation or reaction with the solvent system Thus aliphatic acids decarboxylate to produce mainly fluoroalkanes or products from abstraction of hydrogen from the solvent Perfluoro acids decarboxylate in the presence of aromatic substrates to give perfluoroalkyl aromatics Aromatic and vinylic acids do not decarboxylate [91] (equation 51)... 

Results of studies of the electrocyclic ring opening of 3 fluoro-, 3,3-difluoro-, and 3-tnfluoromethylcyclobutene are consistent with the theoretical predictions of the effect of fluonne on this reaction [142] Surpnsingly, fluonnated analogues of hexa tnene-cyclohexadiene systems undergo complex rearrangements mainly via free radical mechanisms and not by electrocyclic nng operung as expected [143] (equation 35)... 

Almost all of the biomedical research done in the 25 years following the liquid-breathing work was conducted with commercially available fluorocarbons manufactured for various industnal uses by the electrochemical Simons process (fluonnation in a hydrofluoric acid solution) or the cobalt fluoride process (fluori-nation with this solid in a furnace at about 200 C) These processes tended to yield many by-products, partly because they were, to some extent, free radical reactions and partly because it was difficult to easily achieve complete fluonnation Aromatic hydrocarbons gave better products with the cobalt tnfluonde [73] method, whereas saturated hydrocarbons yielded better products with fluonnation using diluted or cooled gaseous fluorine (Lagow) Incompletely fluormated matenal was either... 

Hydrosilylations of fluorine-containing alkenes are free radical reactions initiated by UV light or organic peroxides The direction of addition is the same as with fluonnated alkyl halides However, the reaction between hydrosilanes and fluorine-containing olefins catalyzed by platinum group metal complexes may result in bidirectional addition and/or formation of a vinylic silane, the latter by de hydrogenative silylation[/] The natures of both the silane and the catalyst affect the outcome of the reaction[7] A random selection of some typical new reactions of silanes are shown in Table 1 [1, 2, 3 4]... 

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