Sulfur IV Fluoride

The synthesis is not limited by the amount of S employed. With an initial activity of 10 millicuries of S 04, the 

Isotopic. Sulfur-35 emits j8-particles of 0.167 M.e.v. maximum energy and has a half-life of 87.1 days. It is readily assayed as a solid with a thin-mica-end-window Geiger counter. 

Chemical. In addition to its intrinsic interest, sulfur serves as a starting point for the synthesis of many labeled molecules. Digestion of sulfur in aqueous sulfites yields thiosulfates, which when heated with iodine lead to tetra-thionates and trithionates. Digestion of sulfur in alcoholic cyanide solutions yields thiocyanates, thence thiocyanogen and thiourea with its derivatives and coordination complexes. Oxidation of sulfur to sulfur dioxide is a potential route to labeled sulfamic acid and its derivatives and to labeled sulfuryl chloride. The intermediate sodium sulfide readily yields hydrogen sulfide and metallic sulfides. 

Submitted by F. S. Fawcett and C. W. Tullock Checked by Claude I. MERRiLLf 

Sulfur(IV) fluoride has been prepared by fluorination of elemental sulfur with cobalt(III) fluoride or with elemental 

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Diazoniopheny 1)-1,2-dihydropyridine-2-iminosulfinate, 3392 N, N-Dichloropentafluorosulfanylamine, 4060. S -Dicthylamino(mcthylimino)sulfur(IV) fluoride Diethylaminosulfinyl chloride, 1679 Diethylaminosulfur trilluoride, 1684 SA-Dimcthylpcntasulfur hexanitride, 3647... 

Diazoniophenyl)-1,2-dihydropyridine-2-iminosulfinate, 3386 /V,A-Dichloropentafluorosulfanylamine, 4054 5-Diethylamino(methylimino)sulfur(IV) fluoride, 2021 Diethylaminosulfinyl chloride, 1673 Diethylaminosulfur trifluoride, 1678... 

Phenyltetrafluorophosphorane was first obtained by the reaction of phenyldichlorophosphine with antimony(V) fluoride or a mixture of antimony(V) chloride and antimony-(III) fluoride. In another method of preparation, phenyl-tetrachlorophosphorane was fluorinated with antimony(III) fluoride. Sulfur(IV) fluoride was used to fluorinate both phenylphosphonic acid and phenylphosphonic difluoride under autogenous pressure. Finally, it was found that phenyltetrafluorophosphorane is formed upon reaction of phenyldichlorophosphine with antimony(III) fluoride, by a simultaneous redox and fluorination reaction. " The last reaction is described below. It is very general in scope and has been employed in the synthesis of a wide variety of tetrafluorophosphoranes. " It may be noted that arsenic-(III) fluoride can be employed similarly as the fluorinating agent instead of antimony(III) fluoride. ... 

Diphenyltrifluorophosphorane was first obtained by the reaction of diphenylphosphinic acid with sulfur (IV) fluoride under autogenous pressure. The present method consists in the reaction of diphenylchlorophosphine with arsenic(III) fluoride at atmospheric pressure. ... 

Tri-n-butyldifluorophosphorane was first obtained upon interaction between tri-re-butylphosphine and hexafluoro-thioacetone dimer.The method described here involves the reaction of tri-n-butylphosphine sulfide with antimony-(III) fluoride. The method is more generally apphcable in the synthesis of difluorophosphoranes from tertiary phosphine sulfides. The only previously reported difluoro-phosphorane, triphenyldifluorophosphorane, was obtained by the reaction of triphenylphosphine or triphenylphos-phine oxide with sulfur(IV) fluoride under autogenous pressure. ... 

The first reported preparations of sulfur chloride penta-fluoride involved the fluorination of sulfur(II) chloride, the chlorination of disulfur decafluoride, and the electrolysis of sulfur(II) chloride-hydrogen fluoride mixtures. Newer methods utilize the reaction between chlorine monofluoride and sulfur(IV) fluoride or the reaction between chlorine, cesium fluoride, and sulfur(IV) fluoride. The directions described here for the reaction between chlorine monofluoride and sulfur(IV) fluoride are for the preparation of substantial quantities if only a 1- or 2-g. sample is required, the modifications described in the last paragraph of the Procedure section may be employed or a batch pro-... 

The starting materials, chlorine, chlorine trifluoride, and sulfur(IV) fluoride can be purchased in cylinders and can be used as received. 

Chlorine trifluoride (0.18 l./minute) and chlorine (0.22 l./minute) are mixed together at a T-junction and passed through the first nickel tube, which is maintained at 350°. The gases emerging from this tube are mixed with sulfur(IV) fluoride (0.54 l./minute) and passed into the second reactor, the optimum temperature for which is 375°. Lower temperatures result in incomplete conversion higher temperatures cause the following side reaction to become increasingly important ... 

This simple transformation plays an important rdle in the synthetic organic chemist s ability to selectivity place fluorine atoms into organic molecules. Carbonyl difluoride can be compared with sulfur(IV) fluoride for its effectiveness to replace oxygen. COF, is said to be more... 

Caution. Sulfur(IV) fluoride, sulfur chlorides, and sodium fluoride are toxic chemicals. This procedure should be carried out in a well-ventilated hood with allowance for the fact that vapors heavier than air are involved. 

The crude sulfur(IV) fluoride that collects in the receiver is distilled into the pot of a dry low-temperature glass fractionating column, for example, one having a rectifying section 12 mm. in diameter and 280 mm. in length packed with -in.-i.d. glass helixes and cooled with solid carbon dioxide... 

Methylbromoarsines, synthesis 26 Vanadium(III) fluoride, synthesis 27 Sulfur(IV) fluoride, synthesis 33 Peroxydisulfuryl difluoride, synthesis 34 Trichloro(tripyridine)chromium(III), synthesis 36 Tris(3-bromoacetylacetonato)chromium(III), synthesis 37 Trichloro(tripyridine)molybdenum(III), synthesis 39 Uranyl chloride 1-hydrate, synthesis 41 Rhenium(III) iodide, synthesis 50 Potassium hexachlororhenate(IV) and potassium hexa-bromorhenate(IV), synthesis 51 Iron-labeled cyclopentadienyl iron complexes, synthesis 54 Inner complexes of cobalt(III) with diethylenetriamine, synthesis 56... 

F4S Sulfur(IV) fluoride, 7 119 FSilicon tetrafluoride, 4 145 FaBr Bromine (V) fluoride, 3 185 FaNb Niobium (V) fluoride, 3 179 FaTa Tantalum (V) fluoride, 3 179... 

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