Normant reagent

Acetylene itself (R = H) undergoes the reaction with R2CuLi instead of the Normant reagent. The use of R containing functional groups has been reported. If the alkyl iodide is omitted, the vinylic copper intermediate 64 can be converted... 

Normant reagents. Vinylmagnesium halides that were previously unavailable are now prepared by reacting the parent vinyl halides with magnesium in tetrahydrofuran. These compounds are called Normant reagents and behave like typical Grignard reagents. 

Scheme 6.74. The use of addition of an organocuprate-magnesimn bromide (Normant) reagent to produce an intermediate that can be converted to a variety of alkenes.

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