[orgopete]

I just read about coupling reactions, by coupling it with "vinyl cuprate", did you mean "vinyl lithium cuprate" (H₂CCH)₂CuLi? Can a Gilman reagent be acetylenyl lithium cuprate? So that it would give cyclohexylacetylene directly. And yet, I couldn't find explanation of bromination-dehydrobromination mechanism..

I didn't know whether an acetylene lithium cuprate would couple or not. I didn't recall whether it was in Bruice, but I was pretty sure the lithium vinyl cuprate was. Bromination is Br2, and dehydrobromination can be effected by KO-tBu or an amide base R2N(-) on the vicinyl dibromide.