Hypofluorites Trifluoromethyl hypofluorite

Isocyanides react with fluorine [75 to yield difluoromethylene imines, which tend to dimerize In an inert solvent, imines accept fluorine fioin trifluoromethyl hypofluorite [76, 77] (equation 11)... 

Although fluonnation of peroxoanions [S2] has been examined, the major emphasis in the fluonnation of oxygenated material is the preparation offhioroxy compounds The simplest, trifluoromethyl hypofluorite, can be prepared almost quantitatively by the action of fluorine on carbonyl fluoride (fluorophosgene) in the presence of various catalysts [Si, 84] Addition of fluorine to trifluoroacetic acid [S5] or its sodium salt [S6] gives rise to FjCF(OF)2 Long-chain fluoroxy compounds can also... 

In addition, fluonne [97, 98], trifluoromethyl hypofluorite [99, 100], bisftri-fluoromethyOperoxide [100, 101], trifluoromethyl disulfide [100]. and xenon difluoride [102, lOi, 104] react with phosphines to give the corresponding diflu-orophosphoranes in yields ranging from 25% to near quantitative. Phosphites are fluorinated by carbonyl fluoride [95, 96] or 2-hydroperfIuoropropyl azide [f05J (equation 15). 

Fluoroxytrifluoromethane (trifluoromethyl hypofluorite) and acetyl hypofluorite are the most commonly used neutral hypofluontes, cesium fluoroxysultate is an inorganic anionic fluoroxy derivative... 

Fluorination. Direct fluorination of quinoline was accompanied by extensive fragmentation of the heteroring, but trifluoromethyl hypofluorite in trichlorofluoromethane at -70°C converted 5-fluoro-8-hydroxyquino-line into the 5,7-difluoro-8-hydroxy product (72JMC987). Quinoline, itself, was perfluorinated by fluorine and cobalt(III) fluoride (56JCS783), whereas cesium tetrafluorocobaltate at around 350°C converted it into a mixture of saturated polyfluoro compounds (82JFC413). It is much more satisfactory to introduce fluorine by nucleophilic methods. 

Fluorine Nitrogenous bases Trifluoromethyl hypofluorite Pyridine See other organic bases... 

Perfluoro-tert-butyl peroxyhypofluorite, 1373 Tetrafluoroiodosyl hypofluorite, 4356 Trifluoromethyl hypofluorite, 0353... 

Tetrafluoroammonium hexafluoromanganate, 4384 Tetrafluoroammonium hexafluoronickelate, 4385 Tetrafluoroammonium hexafluoroxenate Tetranitromethane, 0546 Titanium tetraperchlorate, 4170 1,1,1 -Triacetoxy-1,2-benziodoxol-3-one, 3610 Trifluoromethyl hypofluorite, 0353 Trimethylsilyl chlorochromate, 1301 Trioxygen difluoride , 4323 Uranium hexafluoride, 4375 Vanadium(V) oxide, 4866 Vanadium trinitrate oxide, 4763 Vanadyl perchlorate, 4152 Xenon hexafluoride, 4377 Xenon(II) pentafluoroorthoselenate, 4382 Xenon(II) pentafluoroorthotellurate, 4383 Xenon tetrafluoride, 4353 Xenon tetrafluoride oxide, 4346 Xenon tetraoxide, 4863 Xenon trioxide, 4857 Zinc permanganate, 4710... 

Nitryl hypofluorite, 26 128, 130 Nitryl(trifluoromethyl) peroxide, 16 135 N—Li bond, 37 63-65 length... 

Trifluoromethyl [ F]hypofluorite Acetyl [ F]hypofluorite Perchloryl f Flfluoride Xenon d/[ F]fluoride 1-[ F]Fluoro-2-pyridone AZ-f FlFluoropyridinium triflate A/-[ F]Fluoro-A/-alkylsulphonamides Bromo [ F]fluoride... 

R.D. Neirincks, R.M. Lambrecht, A.P. Wolf, Cyclotron isotopes and radiopharmaceuti-cals-XXV An anhydrous F-fluorinating intermediate-trifluoromethyl hypofluorite, Int. J. Appl. Radiat. Isot. 29 (1978) 323-327. 

Trifluoromethyl hypofluorite was first made by Cady by passing methanol [184] or carbon monoxide [185, 186] with fluorine over silver difluoride at elevated temperatures. Later, trifluoromethyl hypofluorite and higher perfluoroalkyl hypofluorites were prepared by treating the appropriate carbonyl compound with fluorine in the presence of dry caesium fluoride at sub-zero temperatures (Fig. 81) [187-189]. 

Trifluoromethyl hypofluorite (see Houben-Weyl, Vol. E14a/3, pp 629 630) is a gas (bp 178 K) which can be prepared from carbonyl derivatives (CO, COF2, MeOH) and fluorine in the presence of various catalysts (AgF2, CsF, etc.).1-5... 

Trifluoromethyl hypofluorite is generally used at low temperatures with reactants dissolved in an inert solvent, but to increase the solubility of reactants a cosolvent (MeOH, acetone, THF) is often used however, it must be used with extra caution and appropriate safety precautions against explosions and fires, since trifluoromethyl hypofluorite is a powerful oxidizing agent. The toxicity of trifluoromethyl hypofluorite is expected to be high (as with fluorine). Fluori-nation reactions with trifluoromethyl hypofluorite have been discussed in the last twenty years in review papers6 11,65 and several monographs.12" 14... 

Barton and co-workers have explored tertiary carbon atom functionalization by trifluoromethyl hypofluorite, mainly in chloroform, on various steroid derivatives however, the site of functionalization strongly depends on the structure of the steroid and the functional group.16-18 e.g. formation of 2. 

Trifluoromethyl hypofluorite reacts with various sulfides in trichlorofluoromethane at — 78 C forming difluoro- 624 and tctrafluorosulfancs 7,25 while fluorodesulfuration is observed in the reaction of amino acids, e.g. formation of 8.26 In a similar manner, trivalent phosphorus compounds react with trifluoromethyl hypofluorite to give difluoro-substituted derivatives 9.27... 

The reaction of trifluoromethyl hypofluorite with various alkenes depends on the structure of the alkene and the reaction conditions.66 67 Hexafluoropropene, various substituted ethenes and fluoro-substituted ethenes usually give two types of products, e.g. 10 and 11, 12A and 12B, and 14 and 15, which are formed via radical intermediates.2-3-28-29... 

Barton and co-workers have studied30 the reactions of trifluoromethyl hypofluorite with various alkenes and found that (Z)- and (T -stilbene give vicinal fluoro trifluoromclhoxy products and vicinal difluorides in chlorotrifluoromethane or diethyl ether, while vicinal fluoro methoxy adducts predominate when the reaction is carried out in methanol at —78 C. svn Addition predominates in all cases on the basis of the fluorination regioselectivity of many alkenes, the formation of a /1-fluoro carbcnium ion is proposed.30... 

When ketones, aldehydes and esters are transformed to silyl enol ethers, further reaction with trifluoromethyl hypofluorite gives a-fluoro carbonyl products 16 in good to excellent yield.31... 

Styrene and 1,1-diphenylethene are frequently used as target molecules in investigations of the role of reagent structure on its reactivity toward organic compounds. Low-temperature fluorination with trifluoromethyl hypofluorite gives up to six products.32-33 The Hammett correlation value q was established to be — 2.48 and a mechanism suggested in which spin-paired free-radical pairs arc formed, which are then converted by electron transfer into an ion pair.33... 

Studies on acetylenic molecules have been less extensive than those on alkenes diphenylacety-lene is converted at — 78 °C in Freon in the presence of calcium oxide with 2.5 equivalents of trifluoromethyl hypofluorite into l,l,2-trifluoro-l,2-diphenyl-2-(trifluoromethoxy)ethane (31) in 75% yield.37... 

Benzene (32, R = H) reacts under photochemical conditions with trifluoromethyl hypofluorite giving fluorobenzene as the main product together with (trifluoromethoxy)benzene,15 while the reaction with toluene (32, R = Me) also gives sidc-chain-substituted products.2,3,15... 

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