The preparation and properties of some 2-amino-1,3,2-dioxaborolanes, (R = R′ = Me; R = H and R′ = Me, Et, Pr′, Bun, Bui, But and Ph) are described and their association is discussed. Reaction of phenyl isocyanate with 2-dimethylamino-1,3,2-dioxaborolane is exocyclic showing that the relative migratory aptitude is R2N > OR.