Borane to Boryl Hydride to Borylene Dihydride: Explicit Demonstration of Boron-to-Metal a-Hydride Migration in Aminoborane Activation

摘要

The sequence of fundamental steps implicit in the conversion of a dihydroborane to a metal borylene complex have been elucidated for an [Ir(PMe_3)_3] system. B-H oxidative addition has been applied for the first time to an aminodihydroborane, H_2BNR_2, leading to the generation of a rare example of a primary boryl complex, L_n(H)M{B(H)NR_2}; subsequent conversion to a borylene dihydride proceeds via a novel B-to-M Ct-hydride migration. The latter step is unprecedented for group 13 ligand systems, and is remarkable in offering a- substituent migration from a Lewis acidic center as a route to a two-coordinate ligand system.