DFT Studies on the Mechanism of Palladium(IV)-Mediated C–H Activation Reactions: Oxidant Effect and Regioselectivity

A series of density functional theory
calculations have been employed
to study the PdIV-mediated C–H activation in CD3CN solvent. B3LYP/DZVP, B3LYP/BS1, and B3LYP-D3/DZVP were
comparatively employed to locate the geometric parameters of possible
stationary points, with IDSCRF radii constituting the cavity. The
novel reaction mechanism provided was divided into three distinct
steps: oxidation addition, ligand substitution, and C–H activation.
The distinct chemical behaviors of different oxidants have been addressed
with Bader’s atoms-in-molecules wave function analysis, providing
a reasonable explanation for the experimental observation. Regioselectivity
was dynamically controlled by the rate-determining oxidation step.
At the same time, the basis set effect was also discussed for this
PdII → PdIV transformation.