Paramagnetic Active Site Models for the Molybdenum--Copper Carbon Monoxide Dehydrogenase

New paramagnetic, heterobimetallic Mo/Cu complexes featuring the Mo(O)(μ-S)Cu core of O. carboxidovorans carbon monoxide dehydrogenase have been synthesized and structurally and spectroscopically characterized. The complexes exhibit EPR spectra (left graphic) indicative of extensive electron delocalization across the Mo-S-Cu core, in agreement with computational studies identifying the singly-occupied molecular orbital (right graphic).