Tertiary alkyl coupling reactions with alkenyl halides

The Corey—Posner, Whitesides—House reaction involves the coupling of a hthium dialkyl-cuprate (called a Gilman reagent) with an alkyl, alkenyl, or aryl halide. The alkyl group of the lithium dialkylcuprate reagent may be primary, secondary, or tertiary. However, the halide with which the Gilman reagent couples must be a primary or cychc secondary alkyl halide if it is not alkenyl or aryl. 

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