Understanding β-Hydride Eliminations from Heteroatom Functional Groups

Using density functional theory, we investigated detailed aspects of the quintessential organometallic process, β-hydride elimination (BHE). In general, we find that most BHE processes from alkyl functional group β-atoms are facile, while BHE processes from heteroatom functional groups (N and O) are prohibitively high in energy. We present calculated molecular orbitals and atomic NBO charges obtained from snapshots along reaction profiles to present a qualitative overview for how heteroatoms adversely affect these processes. We discuss these results to provide an illustration for how these processes proceed, clarifying a sometimes oversimplified model for these reactions.