Organic halides coupling reaction with organocuprates

In addition to their reactions with acid chlorides, epoxides, and a,P-unsaturated carbonyl compounds (Sections 20.13-20.15), organocuprate reagents (R2CuLi) also react with organic halides R X to form coupling products R-R that contain a new C-C bond. Only one R group of the organocuprate is transferred to form the product, while the other becomes part of RCu, a reaction by-product. 

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