Perfluoroarylcopper reagents

The perfluoroarylcopper reagents react with perfluoroalkylated acid fluorides to give ketones in excellent yields. Solvent, type of organometallic reagent,... 

Perfluoroarylcopper compounds are usually prepared from the corresponding perfluoroaryllithium, -magnesium, or -cadmium reagents and copper(I) halides [257] (equation 175). 

Perfluoroalkylcopper and perfluoroarylcopper compounds are noticeably more thermally stable than the corresponding alkyl and aryl compounds. Solutions of perfluoroalkylcopper compounds in DMSO or DMF are stable up to at least 120°C 200), whereas ether suspensions of alkylcopper compounds decompose at 0°C or below. Similarly, pure pentafluorophenylcopper tetramer decomposes at 210°C-220°C, and a sample has been kept in a Dry Ice chest for 5 years 32). However pure phenylcopper can be kept for no more than a few days, even under nitrogen 73). Solutions of pentafluorophenylcopper reagents containing metal halides in THF have been refluxed for 5 days or more without decomposition (97, 144). Other stable perhaloarylcopper reagents are those in which the aryl moiety is perfluoro(p-phenoxyphenyl) (96), pentachlorophenyl, and 2,3,5,6-tetrachloropyridyl 144), none of which... 

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