Definition: What is Gilman Reagent?

Gilman reagent is an organocuprate reagent consisting of lithium, copper, and alkyl group with the molecular formula [R-Cu-R]⁺Li^– (lithium dialkylcuprate). It is used to synthesize new compounds consisting of carbon-carbon bonds from alkyl, aryl, and vinyl halides. Typically, the SN2 reaction method is employed to obtain the final product. The SN2 reaction mechanism is discussed in another article ^[1-7].

The history of Gilman reagent goes back to the 1930s when American chemist Henry Gilman discovered it and reported it in a 1952 paper.

Preparation of Gilman Reagent

Gilman reagent can be prepared in two steps: First, by adding powdered lithium metal to alkyl halide in pentane solvent. Second, by adding copper(I) bromide to alkyllithium in tetrahydrofuran at −78 °C.

Example of Gilman Reagent Reaction

Gilman reagent is used to synthesize new compounds using SN2 reaction as well as α, β – addition ^[1-3].