Iodine pentafluoride, reactions

The halogen fluorides are binary compounds of bromine, chlorine, and iodine with fluorine. Of the eight known compounds, only bromine trifluoride, chlorine trifluoride, and iodine pentafluoride have been of commercial importance. Properties and appHcations have been reviewed (1 7) as have the reactions with organic compounds (8). Reviews covering the methods of preparation, properties, and analytical chemistry of the halogen fluorides are also available (9). 

Liquid Halogen Fluorides as Reaction Media. Bromine trifluoride and iodine pentafluoride are highly dimerized and behave as ionizing... 

Iodine Pentafluoride. Iodine pentafluoride is produced by the reaction of iodine and fluorine. Because iodine has a high melting poiat, the reaction is either performed ia a solvent or the reaction is maintained at a temperature where the iodine is Hquid. In a continuous process usiug a solvent (104), ca 1% I2 is dissolved iu IF and passed to a reactor where it is contacted with F2 gas. The IF is continuously discharged from the reactor where a small portion is taken off as product and the larger portion of the stream is recycled. 

Trimethylarsine gives a 98% yield of trimethylarsine difluoride when treated with xenon difluoride [102] in fluorotrichloromelhane. and tnsfpentafluorophen-yl)arsine gives a 94% yield of tris(pentafluornphenyl)arsme difluoride after reaction with dilute fluorine in fluorotnchloromethane at 0 C [106] Other trivalent arsenic compounds have also been fluorinated with xenon difluoride [103] In addition, arsines have been oxidatively fluorinated by iodine pentafluoride [107] or electrochemically in 26-34% yield [108]... 

Additions of halogen fluorides to the more electrophilic perfluonnated olefins generally require different conditions Reactions of iodine fluoride, generated in situ from iodine and iodine pentafluoride [62 102 103, /05] or iodine, hydrogen fluoride, and parapeiiodic aud [104], with fluormated olefins (equations 8-10) are especially well studied because the perfluoroalkyl iodide products are useful precursors of surfactants and other fluorochemicals Somewhat higher temperatures are required compared with reactions with hydrocarbon olefins Additions of bromine fluoride, from bromine and bromine trifluonde, to perfluonnated olefins are also known [lOti]... 

Accidental contamination of a tetrafluoroethylene gas supply system with iodine pentafluoride caused a violent explosion in the cylinders. Exothermic reaction of the limonene inhibitor with the contaminant present in the gas cylinders may have depleted the inhibitor and initiated explosive polymerisation. 

Solid iodine, I2, will react with fluorine gas, F2, to form gaseous iodine pentaflu-oride, IF5. In one experiment, a scientist mixed 75.0 g of iodine with 4.00 x 1023 molecules of fluorine and allowed them to react. What is the percent yield if the reaction produced 45.2 g of iodine pentafluoride ... 

Also, IF can be prepared by passing fluorine gas through liquid iodine pentafluoride at high temperature (90°C) and then heating the vapors to 270°C to complete the reaction ... 

Most reactions of iodine heptafluoride are similar to those of iodine pentafluoride, except that it does not undergo any further fluorine addition reactions (See Iodine Pentafluoride). The compound reacts with a number of inorganic substances, forming their fluorides, and forms fluoro-derivatives with organics when in diluted form. 

Iodine Pentafluoride. The controlled reaction of IF5 with dimethyl sulfoxide, Me2SO, was found to be quite violent. Although small scale tests in the cold (0°) proceeded without incident, delayed violent explosions occurred upon scale-up or upon allowing the temp to rise to 10-15°... 

To a stirred solution of 120 ml of methylene chloride, 18 ml of dry pyridine, and 5 ml of iodine pentafluoride maintained at —10°C to —20°C in a Dry Ice-carbon tetrachloride slurry is added a solution of 13.5 gm (0.1 mole) of cumyl-amine in 10 ml of methylene chloride over a 1 hr period. The reaction mixture is stirred for another hour at —10°C, and then for 1 hr at 0°. After this time, water is added to the reaction mixture and stirring is continued until the yellow solid which had formed is dissolved. The lower organic layer is separated and washed in turn with water, 1 N hydrochloric acid, a saturated sodium thiosulfate solution, and again with water. After drying with anhydrous magnesium sulfate and filtration, the product solution is partially evaporated by means of a rotary evaporator at a temperature below 30°C. The brown solid obtained on cooling is separated and recrystallized twice from methylene chloride yield 4.75 gm (17.9%), m.p. 86.9°-88.7°C. 

Bromine monofluoride or iodine monofluoride can be prepared from the corresponding elements in trichlorofluoromethane at — 781 and — 45 C,2,3 respectively. The compounds are unstable and decompose at low temperatures, iodine monofluoridc at — 14 C2,3 and bromine monofluoride, in part, even at — 78 C.1 Therefore, they are used, without separation and purification, in Freon solutions at low temperatures or, most frequently, as stoichiometric mixtures bromine trifluoride/bromine and iodine pentafluoride/iodine. A solution of iodine monofluoride, obtained by bubbling nitrogen-diluted fluorine gas into a suspension of iodine in trichlorofluoromethane at — 75 C, was used for addition to alkene C = C bonds. The reaction is regioselective and in most cases obeys the Markovnikov rule.4 Iodine monofiuoride prepared in situ reacts quite efficiently with steroidal alkenes.4... 

The mixtures bromine trifluoride/bromine and iodine pentafluoride/iodine can be successfully employed to prepare bromo- and iodo-substituted fluoroalkanes by addition to poly-fluoroalkenes. The reactions are carried out, in the presence of catalysts aluminum, aluminum/ aluminum triiodide9 or without a catalyst,10 in steel reactors at room temperature or with heating. In most cases the addition products are obtained in high yield (see Table 1). 

When treated with iodine pentafluoride, triphenylbismuthane gives triphenylbismuth difluoride but no evidence for the formation of bismuth(V) derivatives was found in the reactions with tris(4-fluorophenyl)bismuthane and tris(trifluoromethyl)bismuthane. Fluorine-aryl (or alkyl) exchange takes place in these cases instead of oxidative fluorination.139140... 

I2+ and Sb2Fn ions.790 Crystalline solids that can be formulated as I2+Sb2Fn have also been prepared by Kemmitt et al.780 by the reaction of iodine with antimony or tantalum pentafluoride in iodine pentafluoride solutions. 

Yellow crystals of RuF4 can be synthesized by reaction of [RuF5]4 with iodine and iodine pentafluoride. It has a room temperature magnetic moment of 3.04 BM which drops to 2.51 BM at 88 K.2370 Reaction with water gives Ru02.2000,2370... 

Tetrafluoro(perfluorophenyl)silicates, M [CgF5SiF4]. obtained by the interaction between trifluoro(perfluorophenyl)silanc and metal fluorides MF (M — K. Cs) or tetramethylam-monium fluoride in nonaqueous acetonitrile or diglyme,are excellent reagents for penta-fluoroarylation with formation of pentafluoro-substituted derivatives of benzene. Thus, the reaction of these salts with nitrosonium and nitronium tetrafluoroborates leads to per-fluoro(nitrosobenzene) (14) and perfluoro(nitrobenzenc)(15), respectively, in quantitative yield. In the case of reaction with perfluoropyridine, perfluoro(4-phenylpyridine) (16) (33% yield) and pentafluorobenzene (.37 % yield) arc formed. Reaction of tetramcthylammonium tetrafluo-ro(perfluorophenyl)silicate with bromine or iodine pentafluoride gives the corresponding bro-mopentafluorobenzene and pentafluoro(tetrafluoroiodo)benzene. ... 

The blue solid prepared by Rulf et al. (9) in 1906 and thought to be (SbF5)aI was probably a mixture of an la fluoroantimonate salt, and some Sb(III)-containing material. Pure crystalline la SbaFu has recently been prepared by the reaction of iodine with antimony pentafluoride in liquid sulfur dioxide as solvent (11). After removal of insoluble SbFg, deep blue crystals of la SbaFi were obtained from the solution. An X-ray crystallographic structure determination showed the presence of the discrete ions la and SbaFu . Crystalline solids that can be formulated as la SbaFu and Ia TaaFii have also been prepared by Kemmitt et al. (4) by the reaction of iodine with antimony or tantalum pentafluorides in iodine pentafluoride solutions. 

Thus, making use of (the rather mild oxidant) iodine pentafluoride, iodide can be replaced by fluoride even though soft class B metals strongly prefer iodo to fluoro ligands, hence there would be no reaction of the above iodo(-chloro)metallate with either HF or alkali fluorides. 

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