Sulfur tetrafluoridc

C. For example, reaction of 2-oxopropanoic acid with sulfur tetrafluoridc (20°C, 12 h) gives 1,1,1-trifluoroethane (25) quantitatively.117... 

Treatment of furan-2.4- and furan-2.5-dicarboxylic acid with excess sulfur tetrafluoridc and hydrogen fluoride under forcing conditions results in simultaneous conversion of the carboxylic acid groups into trifluoromethyl groups and addition of two fluorine atoms at C 2 and C5 of the furan ring to give highly fluorinated derivatives of 2.5-dihydrofuran, e.g. formation of... 

The reaction of 5-bromo-2-furoic acid with the sulfur tetrafluoridc/hydrogen fluoride system proceeds under mild conditions and results not only in conversion of the carboxylic acid group but also in addition of two fluorines and replacement or migration of bromine a 1 3.5 mixture of 2,2,5-trifluoro-5-(trifluoromethyl)-2.5-dihydrofuran (10) and 2-(bromodifluoromethyl)-2,5.5-trifluoro-2,5-dihydrofuran (11) is obtained.153... 

When quinizarin (1) and naphthazarin (2) are treated with sulfur tetrafluoridc at high temperatures, not only the carbonyl, but also the hydroxy goups are substituted by fluorine." ... 

Introduction of Three Fluorine Atoms Trifluoromethyl Compounds from Carboxylic Acids with Sulfur Tetrafluoridc... 

For experimental procedures and examples, see Houben-Weyl, Vol. 5/3, pp 88-93. Handling of sulfur tetrafluoride is not easy because of its toxicity and aggessive nature. As materials for reactors, stainless steel. Monel or Hastelloy C should be used. A reactor for routine handling of sulfur tetrafluoridc and hydrogen fluoride has been described. ... 

Sulfur tetrafluoridc/hydrogen fluoride converts diketene into 1,1.1.3,3-pentafiuorobutane in 70% yield.261 The reaction of y-butyrolactone with sulfur tetrafluoride gives 4-fluorobutyryl fluoride or 1,1,1.4-tetrafluorobutane, depending on the reaction conditions.262... 

Table 13. Fluorination of Unsaturated Compounds with Sulfur Tetrafluoridc/Lead(IV) Oxide...

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