Computational analysis of R-X oxidative addition to Pd nanoparticles

Area of Science:

• Catalysis
• Materials Science
• Computational Chemistry

Background:

• Oxidative addition (OA) is crucial for synthetic reactions like Heck and Buchwald-Hartwig amination.
• Previous studies focused on Pd(0) complexes, neglecting OA to palladium nanoparticles (NPs).

Purpose of the Study:

• To investigate the oxidative addition of aryl halides to palladium nanoparticles.
• To compare the OA activity of Pd NPs with traditional Pd(0) complexes.

Main Methods:

• Density Functional Theory (DFT) modeling.
• Semi-empirical metadynamics simulations.
• Analysis of energy profiles for OA to Pd NPs and Pd(0) complexes.

Main Results:

• The edges of Pd NPs' (1 1 1) facets are identified as active sites for OA.
• OA to Pd NPs is both kinetically facile at ambient temperatures and thermodynamically favorable.
• Pd NPs exhibit high activity in direct C-X activation.

Conclusions:

• OA to Pd NPs must be included in catalytic mechanism models for a realistic view.
• Findings support the "catalytic cocktail" concept of dynamic interconversions between catalytic centers.
• This work opens new avenues for catalysis research using Pd NPs.