Xenon trifluoromethyl compounds

S -Mono-, di-, and trifluoro derivatives of methionine and 5-fluoroalkyl derivatives of cysteine are accessible through fluorination. Thus, fluorination of methionine sulfoxide with xenon fluoride, or more easily using DAST, provided 5-monofluor-omethionine. Photochemical trifluoromethylation of homocysteine leads to 5-trifluoromethionine. These S -fluoroalkyl compounds are also available through fluoroalkylation of homocysteine. Thus, the addition of difluorocarbene (formed from Freon 11 (CHF2CI)) affords S -difluoromethionine. ... 

The moderate thermal stability of the xenon fluorosulfates suggested that trifluoromethyl sulfates and even the methyl sulfates might be preparable. Although reactions to produce these compounds did proceed, under control, at temperatures of —20° or lower, the solid products usually detonated at or below room temperatures. The interaction of XeFa with a slight molar excess of HOSO2CF3 in HF has yielded a solid product which is indicated by vibrational spectroscopic evidence to be CFsSOaXeF. 

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