Organocopper complexes reactions

With Lewis acid-organocopper complexes, the question of chemoselecdvity in polyalkenic carbonyl systems was further investigated. The reaction of BuCu BF3 with dienoate (26) led to selective 1,4-addition.641 This result was in contrast with the diorganocuprate, where 1,6-addition was reported (equation 30).64 ... 

A cyclopentadienylcopper-fcr/-butyl isocyanide complex catalyzes the Michael addition of dimethyl methylmalonate to acrylonitrile at room temperature to give an S6% yield of the adduct 249). As the CU2O—BNC complex can also catalyze the addition of indene to methyl acrylate, the intermediate is most likely an organocopper complex. The reactions and kinetic data support the mechanism given by Eq. (118) to (120), involving metalation and nucleophilic attack by the carbanion on the olefin within the complex. Displacement of a solvent ligand by the olefin and coordination of the latter to the copper species are essential features of the mechanism. The rate of reaction is decreased if the compound with the... 

Metallation reactions are used for quantitatively converting a CH-acidic compound with methylcopper or phenylcopper into an organocopper complex ... 

A less convenient route for the preparation of cyclopentadienylcopper-ligand complexes involves the use of Cu(I) oxide. Purification of the organocopper complexes is difficult because of the decomposition products formed by subsequent hydrolysis by H2O produced in the metallation reaction, e.g. ° ... 

It is well known that organocopper complexes (CuR] react with organo-lithium reagents [LiR ] to afford the corresponding cuprates [LiCuRR ] (Eq. 2) and that these reactions are most likely equilibria (2, 26). 

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