Organocuprate reagents:

Organocuprate reagents (other source of carbanion equivalents) are prepared through the reaction of one equivalent of cuprous iodide along with two equivalents of an organolithium reagent shown in figure.

Figure: Formation of organocuprate reagents.

These reagents are helpful in the 1, 4-addition of alkyl groups to α, β-unsaturated carbonyl systems and can as well be reacted with alkyl halides to generate larger alkanes. The mechanism is thought to be radical based.

Figure: Reaction of an organocuprate reagent with an alkyl halide.