Reversible ligand-centered reduction in low- coordinate iron formazanate complexes

Broere, D. L.J., Mercado, B. Q., Lukens, J. T., Vilbert, A. C., Banerjee, G., Lant, H. M.C., Lee, S. H., Bill, E., Sproules, S. and Holland, P. L. (2018) Reversible ligand-centered reduction in low- coordinate iron formazanate complexes. Chemistry: A European Journal, 24(37), pp. 9417-9425. (doi: 10.1002/chem.201801298) (PMID:29663542)

Abstract

Coordination of redox‐active ligands to metals is a compelling strategy for making reduced complexes more accessible. In this work, we explore the use of redox‐active formazanate ligands in low‐coordinate iron chemistry. Reduction of an iron(II) precursor occurs at milder potentials than analogous non‐redox‐active β‐diketiminate complexes, and the reduced three‐coordinate formazanate‐iron compound is characterized in detail. Structural, spectroscopic, and computational analysis show that the formazanate ligand undergoes reversible ligand‐centered reduction to form a formazanate radical dianion in the reduced species. The less negative reduction potential of the reduced low‐coordinate iron formazanate complex leads to distinctive reactivity with formation of a new N−I bond that is not seen with the β‐diketiminate analogue. Thus, the storage of an electron on the supporting ligand changes the redox potential and enhances certain reactivity.

• Item Type: Articles
• Additional Information: This work was supported by The Netherlands Organization for Scientific Research (Rubicon Postdoctoral Fellowship 680-50-1517 to D.L.J.B.) and the National S-22 Institutes of Health (Grant GM-065313 to P.L.H.). K.M. L. thanks the A. P. Sloan Foundation and the National Science Foundation (CHE-1454455) for funding.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Sproules, Dr Stephen
• Authors: Broere, D. L.J., Mercado, B. Q., Lukens, J. T., Vilbert, A. C., Banerjee, G., Lant, H. M.C., Lee, S. H., Bill, E., Sproules, S., and Holland, P. L.
• College/School: College of Science and Engineering > School of Chemistry
• Journal Name: Chemistry: A European Journal
• Publisher: Wiley
• ISSN: 0947-6539
• ISSN (Online): 1521-3765
• Published Online: 17 April 2018
• Copyright Holders: Copyright © 2018 Wiley-VCH GmbH & Co. KGaA, Weinheim
• First Published: First published in Chemistry: A European Journal 34(37):9417-9425
• Publisher Policy: Reproduced in accordance with the copyright policy of the publisher