Reactions of Digallanes with p- and d-Block Lewis Bases: Adducts, Bis(gallyl) Complexes, and Naked Ga⁺ as Ligand

A range of double carbene adducts of digallanes(4) are prepared from an existing double digallane adduct, and their halides are subsequently exchanged, establishing the feasibility of both base and halide-exchange reactions from digallane adducts. Furthermore, a range of digallium species are treated with transition-metal Lewis bases, leading alternatively to oxidative addition products, species with monocoordinate Ga⁺ ligands, and an unusual ditopic metal-only Lewis pair (MOLP). These results underline the manifold and unpredictable chemistry of halogallane species with Lewis bases.