Mapping the Relationship of the Dynamic Active Site and the Activation Barrier for Cross-Coupling Reactions on Geminal-Cu Catalyst

In this work, we elaborate on the configurations, electronic properties, and cross-coupling reaction mechanisms of several (hetero) aryl halides and X-based (X = N, C, O, S) nucleophiles coadsorbed on a novel geminal-Cu sites deposited on the polymeric carbon nitride (Cu g /PCN). All reactants undergo an exothermic dynamic bridge-coupling process accompanied by reconstruction of the Cu–Cu sites. The activation barriers of the reaction, following the order of C–N > C–C > C–O > C–S, are positively associated with the degree of dynamic contraction of the Cu–Cu bond distance during the couplings, which aligns well with the experimental conditions. Overall, because of the quantum primogenic effect, the dynamic change of the geminal–Cu distance acts as a driving force, enabling the efficient coupling reactions on the Cu g /PCN. Unraveling the structure–activity relationship on Cu g /PCN facilitates the development of cross-coupling catalysis.