Organocopper compounds synthesis

The synthesis of allenes from organocopper compounds and acetylenic acetates was... 

Pentafluorophenylcopper is representative of a series of fluori-nated organocopper compounds that are highly soluble in organic solvents, more thermally stable than their hydrocarbon analogs, and useful as synthetic intermediates. " Pentafluorophenylcopper has been used to introduce the pentafluorophenyl groups and as a reagent for an improved Ullman diphenyl ether synthesis. It is... 

Cyanocuprates constitute a class of organocopper compounds that finds applications in organic synthesis.234 They are prepared by the direct reaction of an organolithium reagent and CuCN, with two different types of compounds being prepared depending on the stoichiometry employed the 1 1 ratio leads to RCu(CN)Li compounds whereas the 2 1 mixture affords R2Gu(GN)Li2. The lower- order or 1 1 cyanocuprates usually display the Cu-C-N-Li... 

To date, hundreds of organocopper species have been isolated and characterized. It is beyond the scope of this chapter to discuss the synthesis and structural characterization of these compounds in detail [29]. Here, general structural features, especially those associated with the reactivity of organocopper compounds, are discussed and illustrated by representative examples. 

An entirely different methodology is applied for the synthesis of the closely related organocopper compound [Cu(C6H4NMe2-2)j. This proceeds by way of a stable organocopper-CuBr aggregate [47] (see Scheme 1.8). Although structural characterization of [Cu(C6H4NMe2-2)] was hampered by its insolubility in all common solvents, it most probably has a polymeric structure. 

The chiral organocopper compound (186) adds diastereoselectively to 2-methyl-2-cyclopentenone, allowing the preparation of optically active steroid CD-ring building blocks (Scheme 68).202-204 A related method was applied to a synthesis of the steroid skeleton via an intramolecular (transannular) Diels-Alder reaction of a macrocyclic precursor.203 Chiral acetone anion equivalents based on copper azaeno-lates derived from acetone imines were shown to add to cyclic enones with good selectivity (60-80% ee, after hydrolysis).206-208 Even better ee values are obtained with the mixed zincate prepared from (187) and dimethylzinc (Scheme 69). Other highly diastereoselective but synthetically less important 1,4-additions of chiral cuprates to prochiral enones were reported.209-210... 

G. H. Posner, An Introduction to Synthesis Using Organocopper Compounds, Wiley, Chichester, 1980. 

Diorganocuprates couple readily with vinylic halides and have been employed in the synthesis of some natural products, e.g., fulvoplumieren and Cecropia juvenile hormone (26, 27, 62, 63). Copper-halogen exchange can occur simultaneously 174, 309). Successful coupling reactions of organocopper compounds with vinylic halides are listed in Table VIII. 

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