Bromine fluorosulfate

Reactivity of these materials may vary from quite low for HX (X=F, Cl, Br) and hexafluoroacetone to extremely high in the case of BrF3, and chlorine and bromine fluorosulfates. It should also be noted that the reactivity of many of these compounds could be significantly increased by adding Lewis acids and/or increasing polarity of the media. 

A combination of two effects of F-alkyl groups - a large sterical volume and the strong electron-withdrawing effect - are probably the factors responsible for the extremely low reactivity of the C=C bond in cyclic and internal F-olefins, although these olefins still have the ability to interact with very strong electrophiles such as chlorine and bromine fluorosulfates [8] ... 

The first publication on addition of BrOS02F to several fluoroolefins, which appeared in 1966 [103], was followed by a communication on the reaction of chlorine and bromine fluorosulfate with HFP [97]. This initiated the appearance of a number of papers on the use of halogen fluorosulfates in fluoroorganic synthesis. Most of these publications came from Professor Fokin s group in the former Soviet Union. 

Bromine(III) compounds, 317 [Br(OS02F)]2-, 320 Bromine fluorosulfate, 320 Bromine hexafluoroantimonate, difluoro-, 313 Bromine perchlorate, bis(quinoline)-, 319 Bromine tetrafiuoroborate, bis(quinuclidine)-, 319 Bromine trifluoride, 313, 314 Butane, rflc-p,p -diaminodiphcnyl-alkali metal complexes, 14... 

Chlorine trifluoromethanesulfonate, which is much less stable than the corresponding fluorosulfate was synthesized by the reaction of triflic acid with ClF [35]. In the synthesis of bromine trifluoromethansulfonate, the reaction of C10S02CF3 with Br2 was used [36]. 

In contrast to reaction of CF3S020X (see Eq. 100), addition of C10S02F or BrOS02F to chlorotrifluoroethylene leads to formation of two regioisomers. Reaction of bromine tris (fluorosulfate) with fluoroolefins was reported to pro-... 

The formation of significant amounts of polymeric material, with even a slight excess of TFE, along with formation of dimeric products in reaction with HFP bromine tris (fluorosulfate) is strong evidence in favor of the radical mechanism, which in this reaction may compete with the electrophilic process. 

Cyclopropaniminium salts have been prepared in solution from cyclopropane-1,1-diamines by addition of methyl fluorosulfate, - bromine in liquid sulfur dioxide or dimethylchloronium tetrafluoroantimonate in liquid sulfur dioxide. Bicyclo[4.1.0]heptaniminium salts were obtained in fluorosulfonic acid at — 60 °C from a bicyclo[4.1.0]heptanone aminal or hemiaminal precursor or by the reaction of the corresponding aminal and methyl fluorosulfate in chloroform. A free cyclopropaniminium ion in solution also was assumed to be generated by the interaction of cyclopropanone hemiaminal with titanium(IV) chloride at — 78°C in di-chloromethane. ... 

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