Fluorosulfate derivatives

These products are precursors of perfluoro carboxylic acids while the fluorosulfates derived from secondary and tertiary hydrofluorocarbons provide... 

These products are precursors of perfluoro carboxylic acids while the fluorosulfates derived from secondary and tertiary hydrofluorocarbons provide perfluoro ketones, and starting from the IH-perfluoro bicyclo[2.2.1]heptane, the corresponding perfluoro teriaiy alcohol is... 

Derivatives. The nonmetaHic inorganic derivatives of fluorosulfuric acid are generally made indirectly, although complex fluorosulfates of the Group 15 (V) elements and of xenon can be made directly (85,86), as can the NO" and NO" 2 salts (26,27). 

N P Cl (NEt2) 2 (as monitored by F nmr and glc) with antimony trifluoride gives the cis non-geminal difluoride while the use of potassium fluorosulfate gives the cis geminal difluoride. The tetrafluoro derivative, cis-2,4-N P F (NEt, ) can be obtained from... 

Since the discovery of the first noble gas compound, Xe PtF (Bartlett, 1962), a number of compounds of krypton, xenon, and radon have been prepared. Xenon has been shown to have a very rich chemistry, encompassing simple fluorides, XeF2> XeF, and XeF oxides, XeO and XeO oxyf luorides, XeOF2> XeOF, and Xe02 2 perxenates perchlorates fluorosulfates and many adducts with Lewis acids and bases (Bartlett and Sladky, 1973). Krypton compounds are less stable than xenon compounds, hence only about a dozen have been prepared KrF and derivatives of KrF2> such as KrF+SbF, KrF+VF, and KrF+Ta2F11. The chemistry of radon has been studied by radioactive tracer methods, since there are no stable isotopes of this element, and it has been deduced that radon also forms a difluoride and several complex salts. In this paper, some of the methods of preparation and properties of radon compounds are described. For further information concerning the chemistry, the reader is referred to a recent review (Stein, 1983). 

Recently, Germain et al. have also shown that the indirect anodic oxidation in fluorosulfuric add of fluorocarbon derivatives of the type RfCF2X (X — H, COOH, S03H, CH2OH, Br), which are not directly oxidizable, leads to fluorosulfates of the type FSG3CF3Rf (Eqs. 18 and 19) [37, 38], in these reactions, the peroxide (FS03)2, partially dissociated in its free radicals, is the in-situ electrochemically produced reactive intermediate as shown in Scheme 5.1. 

The conversion of some carbohydrate chlorosulfates into the corresponding fluorosulfates with silver fluoride in methanol,31 and the formation of a mono(azi-dosulfate) derivative on treatment of methyl 4,6-dichIoro-4,6-dideoxy-a-D-galac-topyranoside 2,3-di(chlorosulfate) (8) with sodium azide in N,N-dimethylform-amide at room temperature,32 are two other examples of reactions involving sulfur-chlorine scission. 

Another interesting use of the imidazylate gr up in the furanoside series has been described by Tann et al. [89]. Thus, treatment of the C-2 imidazylate ester of the a-D-ribofuranoside tribenzoate derivative with KHF2 and HF, at 160°C, led to the 2-deoxy-2-fluoro sugar in 63% yield, presumably through the intermediacy of the fluorosulfate ester (HPLC). The 2-fluoro compound is a key intermediate in the preparation of 2 -fluoro-2 -deoxy D-arabinofuranosyl pyrimidine nucleosides, which exhibit powerful antiherpetic activity [89] (Scheme 12). 

Alkylation of tellurapyrones 22 (82JOC5235 86MI2 87JOC2123) and tellurachromones 55 (83JA883 88MI4) with ethyl fluorosulfate occurred at the carbonyl oxygen atom of 4-alkoxy derivatives of 25a and 75. 

Covalent fluorosulfates are often used as starting materials for trifluoromethyl sulfate derivatives. Complete degradation of S03F moieties by HS03CF3 is the... 

The main use of CF3SO3H in synthetic inorganic chemistry reported to date has been in preparation of binary compounds which are themselves triflates or of complexes derived from those triflates. HSO3F has been used similarly in the generation of fluorosulfates and of fluorosulfato-complexes but it has also been the medium of choice, particularly when coupled with the oxidant S206F2, in the generation and characterisation of many homopolyatomic cations and transition metal carbonyl cations, as will be shown in Sec. 11.3.4. 

In earlier studies, we prepared [1] the salt Cg SOgF from pyrolytic graphite and the first salt of layer boron nitride by exploiting the powerfully oxidizing fluorosulfate radical which derives from peroxydisulfuryldifluoride,... 

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