Reaction of Molecular Oxygen with an NHC‐Coordinated Pd⁰ Complex: Computational Insights and Experimental Implications

O2 activation: Computational studies of the reaction of O2 with an [(NHC)2Pd0] (NHC=N-heterocyclic carbene) complex reveal an unexpectedly small driving force for formation of a PdII(η2-O2) product. This result led to experimental demonstration of reversible O2 coordination to the (NHC)2Pd center. Computational analysis of the reaction coordinate reveals that O2 reacts with Pd0 through a stepwise mechanism involving an η1-O2 transition state.