Three Reaction Channels with Signature Proton Transfers in the Ni(I)-Catalyzed Decomposition of Ethyl Acetate

The decomposition
of ethyl acetate catalyzed by Ni­(I) has been
investigated in the gas phase both experimentally and computationally.
This approach allows us to determine what is the bare effect of the
metal center in the catalytic process, without the intervention of
environmental factors such as solvent, ligands, counterions, etc.
This reaction is found to exhibit three competitive channels affording
different products: ketene or ethanol, two units of acetaldehyde,
and acetic acid or ethylene. Interestingly, each of these channels
involves a characteristic hydrogen shift as the key step on the catalytic
process: an inner-sphere H shift, an outer-sphere shift, and a peculiar
orbital-like motion that merits careful characterization.