Hydroxyl fluonne

Perfluoropmacol reacts with sulfur tetrafluonde in an unconventional way instead of replacement of the hydroxyl groups by fluorine, the substitution of four fluonne atoms in the sulfur tetrafluonde molecule with oxygen occurs to give the corresponding spirosulfurane [J6J] (equation 79)... 

The reaction of diethyl tartrate with sulfur tetrafluonde at 25 °C results in replacement of one hydroxyl group, whereas at 100 °C, both hydroxyl groups are replaced by fluonne to form a,a -difluorosuccinate [762] The stereochemical outcome of the fluonnation of tartrate esters is retention of configuration at one of the chiral carbon atoms and inversion of configuration at the second chiral center [163,164, 165] Thus, treatment ofdimethyl(+)-L-tartrate with sulfur tetrafluonde gives dimethyl meso-a,a difluorosuccinate as the final product [163, 164], whereas dimethyl meso tartrate is converted into a racemic mixture of D- and L-a,a -difluorosuccmates [765] (equation 80)... 

Fluonnated alkenes with one fluonne atom attached to the double bond are converted to a-hydroxyketones by potassium permanganate [30] (equation 22) a-Diketones are formed by permanganate hydroxylation of double bonds flanked by fluonne atoms [31] (equation 23)... 

A nitro group in the artho or para position to fluonne is known to enhance its replacement by hydroxyl [II, 12] Bromine and iodine are much less prone to hydrolysis under similar conditions The effect is much less pronounced with the meta nitro derivative (equation 11) With o-nitro-p-fluoroaniline, it is the amino group ortho to the nitro group, rather than meia fluorine, that is replaced by hydroxyl (equation 12)... 

In an unusual example of displacement of fluonne by hydroxyl, hydroxyl radicals attack fluorinated benzenes Hexafluorobenzene is the least reactive The hydroxyl radical generates the pentafluorocyclohexadienonyl radical from it [13] (equation 13) These unstable species are detected spectroscopically Their disap-... 

Oxygen nucleophiles (hydroxyl or nitrite) readily replace fluonne mperfluor-inated systems [10, II] (equations 6 and 7). 

When pentafluoromtrobenzene reacts with ortho- or para-ammophenol m dimethylformarmde solution contaimng sodium hydroxide, the 4-fluonne is replaced. Either the amino or the hydroxyl function of the armnophenol can act as the nucleophile dependmg on the reaction conditions [67] (equation 35)... 

One of the most useful ways of introducing fluonne into organic compounds is the replacement of the hydroxyl group in alcohols hydroxy compounds, and carboxylic acuis Methyl alcohol reacts with anhydrous hydrogen fluoride at 100 500 C in the presence of aluminum fluoride [60, 6J], zinc fluoride [62] chromium fluonde [63], or a mixture of aluminum and chromium fluondes [64] to give a 20-78% yield of fluoromethane Attempted fluorinations of higher alcohols by this method failed [60]... 

Hydroxylation, the addition of two hydroxyl groups across a double bond, converts fluonnated alkenes to different products depending on the presence or absence of a fluonne atom at the hydroxylated carbon... 

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