Dative bonding between group 13 elements using a boron-centered Lewis base

An electron-rich monovalent boron compound is used as a Lewis base to prepare adducts with group 13 Lewis acids using both its boron and nitrogen sites. The hard Lewis acid AlCl3 binds through a nitrogen atom of the Lewis base, while softer Lewis acids GaX3 (Cl, Br, I) bind at the boron atom. The latter are the first noncluster Lewis adducts between a boron-centered Lewis base and a main-group Lewis acid.