Heptafluoropropane, reaction

This mechanism was suggested for the reaction of 1,3-dichlorotetra-fluoropropene with F which gives 1,1,1,2,3,3,3-heptafluoropropane, by nucleophilic addition of F to the substitution product equations 25-27) (Miller et al., 1960). 

The reaction of carbon disulfide with heptafluoropropane under phase-transfer conditions provided bis-(trifluoro-methylidene)-l,3-dithietane 188 (the yield was not reported) (Equation 33) <1997JFC(82)29>. 

The strong inductive effect of the heptafluoropropyl group facilitates the reaction of the compound with hydroxide anion at the aldehyde carbon. In an SN2 reaction, the leaving group is heptafluoropropyl with its electron pair. Protonation of the anion gives heptafluoropropane L and potassium formate [60]. 

It was noted that for the perfluorobutanoic acid salts of the alkaline earth metals the yield of perfluoroalkene increased with increasing weight of the metal cation (vide supra).62 Decomposition of the barium salt gave hexafluoropropene in 78% yield while the reaction with the magnesium salt gave > 5 % of the same product. An exception was ammonium per-fluorobutanoate (4) which formed no alkene, but instead gave an almost quantitative yield of 1,1.1,2,2,3,3-heptafluoropropane (5).68 This reaction is equivalent to the decarboxylation of perfluoro acid salts in protic media. In this case the proton is donated by the ammonium ion. 

Chemically inhibits combustion chain reaction Ordinary commodities Flammable and combustible liquids Electrical fires Metals Materials that react with heptafluoropropane Sealed compartments required for total flooding systems May generate corrosive byproducts when exposed to fire Concentrations required for extinguishment are not immediately lethal Readily dispersed Electrically non-conductive Self-pressurizing agent Environmentally benisn... 

Recently the direct synthesis and the stability of perfluoro-w-propyl-lithium has been the subject of a careful study (8). Although heptafluoro-propyl iodide does not react with lithium metal in pentane or diethyl ether at temperatures between —50° and 20° C, a vigorous reaction occurs at —74° C between the iodide and lithium containing 2% sodium when diethyl ether is the solvent. Among the reaction products are hexafluoropropene, fluorine-containii pol)rmers, andatraceof heptafluoropropane. Formation of heptafluoropropane can be understood in terms of hydrogen abstraction from the solvent by perfluoro-n-propyllithium, while hexafluoropropene could form by the reactions,... 

After one mole of heptafluoropropyl iodide has been added to one mole of lithium aluminum hydride, further addition of the iodide leads to formation of heptafluoropropane but no additional hydrogen [reaction (b)]. A third mole of heptafluoropropyl iodide reacts more slowly, in accordance with reaction (c). Only after addition of 3 moles of heptafluoropropyl iodide to the original one mole of lithium aluminum hydride did the resulting ethereal solution fail to liberate hydrogen upon addition of water. 

Perfluoro-n-propylzinc iodide was characterized by the release of heptafluoropropane on addition of aqueous reagents, and by reaction with acetyl chloride to give the ketone, CH3COC3F7. Perfluoro-n-propylzinc iodide however, does not react with carbon dioxide, and in general, appears to be less reactive than perfluoro-n-propylmagnesium iodide. 

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