Impact of chalcogen identity on the properties of Fe/Co/Ch clusters.

Herein, we report the synthesis and characterization of Fe3Co6S8L6 (L = Ph2PN(-)Tol), a sulfide analogue of the previously reported selenide cluster Fe3Co6Se8L6. Structural, spectroscopic, and electrochemical studies reveal that substitution of Se with S contracts the cluster core, increases the affinity for exogenous ligand binding at the Fe edge sites, and leads to a dramatic increase in the catalytic activity towards asymmetric carbodiimide formation from tosyl azide and tert-butyl isocyanide.