Transition Metal Catalyzed Alkylation at sp^3-, sp^2-, and sp-Carbons

Transition metal catalyzed alkylation reactions resulting in cross-coupling and multicomponent-coupling are described. These reactions proceed efficiently under mild conditions using a combination of transition metal catalysts and alkyl (pseudo)halides in the presence of Grignard reagents and represent the practical routes to the alkylation of sp3-, sp2-, and sp-carbons. Anionic transition metal complexes play important roles as active catalytic species for SN2 and electron transfer processes in reactions with alkyl halides. The carbometalation of C-C unsaturated bonds with alkylmetal species is also a promising tool for the introduction of alkyl groups.