87996-54-1Relevant articles and documents
Acylation du trifluoromethoxybenzene en catalyse HF-BF3
Desbois, Michel
, p. 885 - 890 (2007/10/02)
Friedel and Crafts acylation of trifluoromethoxy- and trifluoromethyl-thiobenzene fails to give ketones in a one step synthesis if chlorinated Lewis acids (AlCl3) are used, because of halogen exchange on the -OCF3 and -SCF3 groups.The use of a fluorinated catalyst system such as HF-BF3 avoids exchange reactions and acylation occurs smoothly under mild conditions: - Low temperature and pressure - High yields (very often >90 percent) - Very high para-regioselectivity.Related reactions such as formylation or sulfonylation can also be achieved under similar conditions.
Process for the preparation of α,α-difluoroalkyl-thiophenyl ketones
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, (2008/06/13)
A process for the preparation of α,α-difluoroalkoxy or α,α-difluoroalkylthiophenyl ketones, in which a polyhaloalkoxybenzene or a polyhaloalkylthiobenzene is reacted with a carboxylic acid, a precursor or a derivative of this acid in the presence of boron trifluoride in such an amount that the absolute pressure of the boron trifluoride within the reaction vessel exceeds 1 bar, and in the presence of hydrofluoric acid as a solvent. The resultant products are useful as intermediates in the synthesis of compounds having phytosanitary (e.g., herbicidal) or pharmaceutical activity.
