Thionyl fluoride, reaction with

Thionyl fluoride, as by-product in sulfur tetrafluoride reactions, 41, 105 toxidty of, 41,105 Thiophene-2-OL, 43, 55 2(5H)-Thiophenone, 43, 55 Thiosemicarbazide, in synthesis of 1,2,4 triazole, 40, 99 reaction with formic acid to yield l-formyl-3-thiosemicarbazide, 40,99... 

Thiocarbonyl tetrachloride, i6, 21 Thionyl chloride, 45, 16, 98 Thiophosgene, 45, 21 Thiophosphoryl chloride, reaction with methylmagnesium bromide to yield tetramethylbiphosphine disulfide, 45,102 Toluenesulfonybromide, 46, 88 Trichloroacetyl fluoride, 46, 6 1,1,3-Trichloiio- -nonane, 46,104 Tricyclo[2.2.1.0 ]heptan-3-ol, 45,... 

Reaction with hydrofluoric acid forms sulfurous oxyfluoride (thionyl fluoride), SOF2 ... 

Solid sulphur, selenium, and tellurium inflame in fluorine gas at ordinary temp. sulphur burns to the hexafluoride, SF6. The reactivity of sulphur or selenium with fluorine persists at —187°, but tellurium is without action at this temp. Hydrogen sulphide and sulphur dioxide also burn in the gas—the former produces hydrogen fluoride and sulphur fluoride. Each bubble of sulphur dioxide led into a jar of fluorine produces an explosion and thionyl fluoride, S0F2, is formed but if the fluorine be led into the sulphur dioxide, there is no action until the sulphur dioxide has reached a certain partial pressure when all explodes. If the fluorine be led into an atm. of sulphur dioxide at the temp, of the reaction, sulphuryl fluoride, S02F2, is formed quietly without violence. Sulphuric acid is scarcely affected by fluorine. 

Thionyl fluoride can be prepared by the reaction of thio-nyl chloride with metal fluorides such as zinc(II) fluoride1 and arsenic (III) fluoride,2 and with metal fluorosulfites.3 It is also obtained by the action of hydrogen fluoride upon a mixture of tetrasulfur tetranitride and copper(II) oxide4 and by the reaction of hydrogen fluoride with thionyl chloride in the absence of6 or in the presence of6 antimony(V) fluoride as catalyst. Another method and the simplest on a laboratory scale involves the reaction of antimony(III) fluoride with thionyl chloride in the presence of antimony ) chloride as catalyst.7 This last procedure is described below. 

Reaction of the j8-hydroxysilanes with thionyl chloride in triethylamine followed by treatment with fluoride, or with potassium hydride or tert-butoxide, leads to elimination of both the hydroxy and silyl groups and to the formation of alkylidenecyclopropanes (see Section 52.2.1.2). 

A study of the reaction of fluorine with SO2 has shown that at temperatures up to 500 °C the reaction rapidly gives sulphuryl fluoride. If the quantity of fluorine is large enough, then SFe is formed, but only slowly, and via the formation of thionyl fluoride, thionyl tetrafluoride, and pentafluorosulphur hypo-fluorite. The fluorination of SO2 by Xep2, in the presence of compounds of the type MX (M = NMe4, Cs, or K X = F or Cl), has been studied. A variety of products were observed (Table 2) and reaction mechanisms were proposed in which the Xep2 functions as a weak Lewis acid. 

Thionyl fluoride was first prepared by Meslans (207) in 1896 and four years later it was described in more detail by Moissan and Lebeau (216, 217) who produced it by the reaction of thionyl chloride with fluorine or... 

Moissan and Lebeau (1902) mixed fluorine and thionyl fluoride at room temperature and obtained a new product. From the change in pressure during the reaction they considered the product to have the formula SOF4. They did not definitely identify the substance (217). The substance was prepared and studied in the laboratory of O. Ruff in 1937 but the work was not published until after World War II. The reaction of Fa with SOF2 took place in the presence of platinum at about 150° (165, 17A). Thionyl tetrafluoride has also been produced from SOF2 and F2 in a copper tube reactor packed with a fluorinated copper, AgF2 catalyst (78). 

---