Preparation of Organofluorine Compounds: Exploring Mono-, Di-, and Tri-fluorination

Organofluorine compounds exhibit biological activity and have advantageous properties for drug design. Natural occurring fluorinated molecules are rare, demanding new synthetic methods for their preparation. A novel route to access trifluoromethyl ketones from Weinreb amide precursors is discussed. This is the first documented method for the use of the Ruppert-Prakash reagent, (trifluoromethyl)trimethylsilane, for the production of trifluoromethyl ketones from amide starting materials. This method is tolerant of aryl and alkyl substrates exhibited by their moderate to excellent yields. A discussion of the unusual reactivity of these amides, their selectivity for mono-trifluoromethylation, and other mono-, and di-fluorination attempts are reported.