CARBENE ADDUCTS OF MAGNESIUM AND ZINC

The syntheses and characterizations of adducts of dialkylmagnesium and dialkylzinc with nucleophilic carbenes are described. These carbene adducts are available directly from the reaction of the stable nucleophilic carbenes 1,3-dimesitylimidazol-2-ylidene or 1,3-di(1-adamantyl)imidazol-2-ylidene and the dialkylmetal compounds. The X-ray crystal structures of the 1,3-di(1-adamantyl)imidazol-2-ylidene.diethylzinc adduct and 1,3-dimesitylimidazol-2-ylidene.diethylmagnesium are reported. The adamantyl substituted carbene gave a monomeric metal adduct whereas the mesityl substituted carbene shows a structure with bridging alkyl groups.