ja6b05480_si_002.cif (1.26 MB)

A One-Hole Cu4S Cluster with N2O Reductase Activity: A Structural and Functional Model for CuZ*

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posted on 29.09.2016, 00:00 by Brittany J. Johnson, William E. Antholine, Sergey V. Lindeman, Michael J. Graham, Neal P. Mankad
During bacterial denitrification, two-electron reduction of N2O occurs at a [Cu44-S)] catalytic site (CuZ*) embedded within the nitrous oxide reductase (N2OR) enzyme. In this Communication, an amidinate-supported [Cu44-S)] model cluster in its one-hole (S = 1/2) redox state is thoroughly characterized. Along with its two-hole redox partner and fully reduced clusters reported previously, the new species completes the two-electron redox series of [Cu44-S)] model complexes with catalytically relevant oxidation states for the first time. More importantly, N2O is reduced by the one-hole cluster to produce N2 and the two-hole cluster, thereby completing a closed cycle for N2O reduction. Not only is the title complex thus the best structural model for CuZ* to date, but it also serves as a functional CuZ* mimic.