A living library concept to capture the dynamics and reactivity of mixed-metal clusters for catalysis

Abstract

The exploration of ligated metal clusters’ chemical space is challenging, partly owing to an insufficiently targeted access to reactive clusters. Now, dynamic mixtures of clusters, defined as living libraries, are obtained through organometallic precursor chemistry. The libraries are populated with interrelated clusters, including transient and highly reactive ones, as well as more accessible but less reactive species. Their evolutions upon perturbation with substrate molecules are monitored and chemical information is gained without separation of the clusters. Here we prepared a library of all-hydrocarbon ligated Cu/Zn clusters and developed a bias-free computational framework suited to analyse the full compositional space that yields a reliable structural model for each cluster. This methodology enables efficient searches for structure–reactivity relationships relevant for catalysis with mixed-metal clusters: when treating the library with CO₂ or 3-hexyne and H₂, we discovered [Cu₁₁Zn₆](Cp*)₈(CO₂)₂(HCO₂) bearing a formate species related to CO₂ reduction and [Cu₉Zn₇](Cp*)₆(Hex)₃(H)₃ bearing C₆ species related to alkyne semi-hydrogenation.