A Computational Study on the Capability of Borane-Cyclic Boryl Anion Adducts to Act as Hydrogen Atom Donors

According to our theoretical approaches, a cyclic boryl anion can act as a Lewis base like its isoelectronic counterpart N-heterocyclic carbene, reducing the homolytic bond dissociation energy of B-H in BH3. However, the donating efficiency is affected by the counter cation in both gas phase and nonpolar solvents. Moreover, we also predict the seven-membered ring boryl anion 5, although it has not yet synthesized, to be the most efficient reagent to reduce the bond dissociation energy of a B-H bond in BH3. This study may thus pave another avenue toward Lewis base induced hydrogen atom abstraction in BH3. (C) 2010 Wiley Periodicals, Inc. J Comput Chem 31: 2258-2262, 2010