Fluonne by chlonne

Ruorocarbon solvent polarity (PJ increases when fluonne is substituted by chlonne or hydrogen, and hydrofluorocarbons can be more polar than their hydrocarbon analogues Notably, = 7 52 and P (1,2 C H4p2) = 7 86 vs... 

The carbon-fluonne bond is normally resistant to cleavage by zinc metal so that the carbon-chlonne bond in chlorodifluoromethyl ketones is selecnvely reduced The... 

The reactivity of tetraphenylphosphonium hydrogen difluoride is comparable with more conventional chlonne-fluonne exchange reagents It can be used and regenerated as illustrated in equation 18 and its preparation is outlined in Procedure 3, p 193 The rate of reaction of tetraphenylphosphonium hydrogen difluonde with benzyl bromide using a fluoride concentration of 0 12 M in acetomtnle (f1/2=25 min at 52 °C) can be compared with that achieved by replacing it with potassium fluoride- 18-crown-6 (tm = 11 5 h at 82 °C) [28] The... 

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