Metal/Support Interactions Regulate Substrate Binding in Fe/Co/Se Cluster Catalysts

This study provides atomistic insights into howdistal changes(e.g., the number of neighboring active sites) regulate the affinityfor substrates and tune the catalytic activity toward azide activationand carbodiimide formation at Fe/Co/Se clusters. Here, we investigate the stereoelectronicrequirementsof a familyof Fe/Co6Se8 molecular clusters to achieve aGoldilocks regime of substrate affinity for the catalytic couplingof tosyl azide and tert-butyl isocyanide. The reactivityof a catalytically competent iron-nitrenoid intermediate, observed in situ, is explored toward nitrene transfer and hydrogen-atomabstraction. The dual role of isocyanide, which, on the one hand,prevents catalyst degradation but, in large amounts, slows down reactivity,is exposed. The impact of distal changes (the number of neighboringactive sites and the identity of supporting ligands) on the substrateaffinity, electronic properties, and catalytic activity is investigated.Overall, the study reveals that the dynamic, push-pull interactionsbetween the substrate ((BuNC)-Bu- t ), activesite (Fe), and support (Co6Se8) create a regimewhere increased substrate activation occurs with facile dissociation.

Automated summary

This study provides insights into how distal changes regulate the affinity for substrates and tune the catalytic activity of Fe/Co/Se clusters. The stereoelectronic requirements of Fe/Co6Se8 clusters for substrate affinity are investigated. The impact of distal changes on substrate affinity, electronic properties, and catalytic activity is explored. The study reveals the dynamic interactions between the substrate, active site, and support, and their role in substrate activation.