Interpreting Oxidative Addition of Ph–X (X = CH(3), F, Cl, and Br) to Monoligated Pd(0) Catalysts Using Molecular Electrostatic Potential

[Image: see text] A B3LYP density functional theory study on the oxidative addition of halogenobenzenes and toluene to monoligated zerovalent palladium catalysts (Pd–L) has been carried out using the “L” ligands such as phosphines, N-heterocyclic carbenes, alkynes, and alkenes. The electron deficiency of the undercoordinated Pd in Pd–L is quantified in terms of the molecular electrostatic potential at the metal center (V(Pd)), which showed significant variation with respect to the nature of the L ligand. Further, a strong linear correlation between ΔV(Pd) and the activation barrier (E(act)) of the reaction is established. The correlation plots between ΔV(Pd) and E(act) suggest that a priori prediction on the ability of the palladium complex to undergo oxidative addition is possible from V(Pd) analysis. In general, as the electron-donating nature of ligand increases, the suitability of Pd(0) catalyst to undergo oxidative addition increases. V(Pd) measures the electron-rich/-deficient nature of the metal center and provides a quantitative measure of the reactivity of the catalyst. By tuning the V(Pd) value, efficient catalysts can be designed.