Pentafluorides SbF

Antimony pentafluoride, SbFs, is a colorless, very viscous liquid (mp 8.3 °C, bp 141 °C) formed by reaction of HF with... 

Antimony pentafluoride, SbFs, reacts with Xep4 and XeFs to form ionic compounds XeFj SbFg and XeFs SbFs, respectively. Describe the geometries of the cations and anions in these two compounds. 

Antimony pentafluoride (SbFs) has been shown by various experimental techniques to be by far the strongest Lewis superacid. It is a toxic, corrosive. 

How would we modify the reaction conditions so as to maximize the possibility of generating the carbocation and minimize the chances for its further reaction Antimony pentafluoride (SbFs) is an even stronger Lewis acid than AICI3 toward halogens, particularly fluorine. When SbFs removes a fluoride ion from an alkyl compound the anion antimony hexafluoride (SbFg ) is produced (Fig. 14.109).This anion is nonnucleophilic, and fluoride ion is a poor nucleophile as well. 

Practice Problem A Draw the Lewis structure of phosphorus pentachloride (PCI5). Practice Problem B Draw the Lewis structure of antimony pentafluoride (SbF,). 

Fluorination of o-carborane (1) can be achieved in several ways. Depending on the reaction conditions (temperature, solvent, and the reactants ratio), electrophilic fluorination of 1 in the presence of antimony pentafluoride (SbFs) led to regioselective fluorination producing 9-fluoro- (10),... 

Chlorine trifluoride CIF3 [1749] Bromine trifluoride BrFa [1746] Antimony pentafluoride SbFs [1732]... 

Dry fluorine derivatives such as antimony trifluoride SbFa, antimony pentafluoride SbFs, bromine pentafluoride BrFs, d chlorine trifluoride CIF3 have no action on aluminium, except on alloys with silicon (40000). At 30 °C, the dissolution rate of alloys 1100, 2024, 3003, 5052 and 7079 in chlorine trifluoride is below 1 p,m [8]. 

One of the most strongly acidic solutions known is a mixture of antimony pentafluoride (SbFs) and fluorosulfonic acid (HSO3F). The dominant equilibria are... 

Antimony forms both a trifluoride and a pentafluoride. It also forms the very stable hexafluoroantimonate ion [17111-95-4] SbF present in solution and a number of salts. 

Properties. Antimony pentafluoride [7783-70-2], SbF, is a colorless, hygroscopic, very viscous liquid that fumes ia air. Its viscosity at 20°C is 460 mPa-s(=cP) which is very close to the value for glycerol. The polymerization of high purity SbF at ambient temperature can be prevented by addition of 1% anhydrous hydrogen fluoride, which can be removed by distillation prior to the use of SbF. The pure product melts at 7°C (11), boils at 142.7°C,... 

The only example of xenon in a fractional oxidation state, +, is the bright emerald green paramagnetic dixenon cation, Xe [12185-20-5]. Mixtures of xenon and fluorine gases react spontaneously with tiquid antimony pentafluoride in the dark to form solutions of XeF+ Sb2 F, in which Xe is formed as an iatermediate product that is subsequently oxidized by fluorine to the XeF+ cation (83). Spectroscopic studies have shown that xenon is oxidized at room temperature by solutions of XeF+ ia SbF solvent to give the XE cation (84). 

KrF+ AsF/, KrF+ SbF/, and KrF+ Sb2F, are moderately stable at room temperature. The KrF+ cation ranks as the most powerful chemical oxidizer known (120) and is capable of oxidizing gaseous xenon to XeF/, gaseous oxygen to O2, NF to NF, and chlorine, bromine, and iodine pentafluorides to... 

Antimony Pentafluoride. Antimony(V) fluoride [7783-70-2], colorless, hygroscopic, viscous Hquid that has SbF units with... 

Antimony pentafluoride may be prepared by fluorination of SbF or by treatment of SbCl with HF. In the latter method the fifth chlorine is removed with difficulty failure to remove the chlorine completely results in contamination of the distilled SbF with Sb(III) (27). 

Antimony pentafluoride is a strong Lewis acid and a good oxidizing and fluorinating agent. Its behavior as a Lewis acid leads to the formation of numerous simple and complex adducts. It reacts vigorously with water to form a clear solution from which antimony pentafluoride dihydrate [65277-49-8], SbF 2H2O, may be isolated. This is probably not a tme hydrate, but may well be better formulated as [H O] [SbF OH]. 

Grown Ethers. Ethylene oxide forms cycHc oligomers (crown ethers) in the presence of fluorinated Lewis acids such as boron tritiuoride, phosphoms pentafluoride, or antimony pentafluoride. Hydrogen fluoride is the preferred catalyst (47). The presence of BF , PF , or SbF salts of alkah, alkaline earth, or transition metals directs the oligomerization to the cycHc tetramer, 1,4,7,10-tetraoxacyclododecane [294-93-9] (12-crown-4), pentamer, 1,4,7,10,13-pentaoxacyclopentadecane [33100-27-6] (15-crown-6), andhexamer, 1,4,7,10,13,16-hexaoxacyclooctadecane [17455-13-9]... 

Proton Magnetic Resonance Shifts of t-Butyl Fluoride and its Antimony Pentafluoride Complex (in SbFs)... 

Iodine pentafluoride similar to other halogen fluorides exhibits amphoteric behavior i.e., with strong Lewis acids, such as SbFs, it can form cation, IF4 ... 

The observation of stable alkyl cations in antimony pentafluoride solutions also opened up the possibility of investigating the electronic spectra of these solutions. It has been reported73 that solutions of alkyl cations in HSC F-SbFs solution at — 60°C showed no absorption maxima above 210 nm. In view of this observation, it was resolved that previous claims relating to a 290-nm absorption of alcohols and alkenes in sulfuric acid solutions were due to condensation products or cyclic allylic ions and not to simple alkyl cations.74... 

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