Perfluoroalkylcopper reagents

Table 6, Perfluoroalkyl Aromatic Compounds Prepared via the Reaction of Perfluoroalkylcopper Reagents with lodo-or Bromoaromatic Compounds...

At higher temperatures, an oligomeric mixture of perfluoroalkylcopper reagents IS obtained [272] (equation 142). 

Perfluorovinyl iodides readily undergo stereospecific coupling with the tn-fluoroinethylcopper solution [224] (equation 151) prepared from dibromodifluo-romethane [210] With longer-chain perfluoroalkylcopper reagents, the coupling reaction is accompanied by some exchange processes [225] (equation 152)... 

Perfluoroalkylcopper reagents couple with I-iodnacetylenic derivatives to... 

Perfluoroalkylcopper reagents react with thiocyanates to give perfluoro-alkyl-substituted sulfides in low yields [230] and with benzoylformyl chloride to give the oi-diketone in 49% yield [231] However, other a-ketoacyl halides were prepared in less than 5% yield [231]... 

Perfluoroalkylation of olefins and acetylenes occurs in low yields when perfluoroalkylcopper reagents are heated with alkenes or acetylenes in DMSO [226, 237, 238, 239]. Undine derivatives react similarly [240]... 

The DMF solution of CF3Cu slowly decomposes at room temperature to form pentafluoroethylcopper [92] and at higher temperature to form an oligomeric mixture of perfluoroalkylcopper reagents [93] (Scheme 31). 

Perfluoroalkylcopper reagents couple with 1-iadoacetylenic derivatives to give the expected perfluoroalky(-substituted acetylenes [226] (equation 153) The coupling reaction is complicated by formation of the diyne from competitive exchange processes... 

Allylation is a facile process and will occur with any perfluoroalkylcopper reagents [207, 224] Typical examples are shown below in equations 154 and 155... 

A possible route to secondary perfluoroalkylcopper reagents may be a reaction between a copper(I) halide and a secondary perfluoroalkylsilver compound. The latter are easily prepared by the addition of silver fluoride to a perfluoroolefin in acetonitrile at 25°C 202) [Eq. (26)]. 

Numerous perfluoroalkyl-substituted arenes have been prepared by the coupling of aryl iodides or bromides with perfluoroalkyl iodides in the presence of copper bronze in a dipolar aprotic solvent at elevated temperatures. Perfluoroalkyl bromides and chlorides can be utilized in similar reactions provided a bidentate ligand such as 2,2 -bipyridyl or 1,10-phenanthroline is added 199, 278). Perfluoroalkylcopper reagents are believed to be intermediates in the couplings 200, 201). 

Perfluoroalkylcopper reagents are the most studied perfluoroalkyl organometallic reagents due to their unique combination of thermal stability and chemical reactivity. They are readily prepared by copper metal insertion reactions with perfluoroalkyl halides in a coordinating solvent (e.g., formation of decarboxylation reactions of perfluoroalkanoic acid salts and copper(I) halide (e.g., formation of 2 ), or metathesis reactions (e.g., formation of 4 via 3 ). (Trifluoro-methyl)copper (4) has also been recently accessed by decomposition of methyl 2,2-difluoro-2-(fluorosulfonyl)acetate (5) or methyl perfluoro [2-(fluorosulfonyl)ethoxy]acetate (6) in the presence of copper(I) iodide and by reaction of trimethyl(trifluoromethyl)silane (7) with fluoride and copper(I) iodide. ... 

Perfluoroalkylcopper reagents have received more attention than perhaps any other perfluorinated organometallic compounds. They can be prepared from per-fluoroalkyl iodides and copper metal in polar solvents (such as DMSO, DMS,... 

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