Gilman reagent

A Gilman reagent is a diorganocopper compound with the formula Li[CuR2], where R is an alkyl or aryl.

[5] If the Li+ ions is complexed with the crown ether 12-crown-4, the resulting diorganylcuprate anions adopt a linear coordination geometry at copper.

[6] For the higher order cyanocuprate Li2CuCN(CH3)2, the cyanide ligand is coordinated to Li and π-bound to Cu.

[7] More useful generally than the Gilman reagents are the so-called mixed cuprates with the formula [RCuX]− and [R2CuX]2−.

Thus, in some applications, the mixed cuprate with the formula Li2[Cu(2-thienyl)(CN)R] is prepared by combining thienyllithium and cuprous cyanide followed by the organic group to be transferred.