Four Redox Isomers of a [3 × 3] Copper–Iron Heterometal Grid

Sato, Hiroki; Onuki, Tatsuya; Newton, Graham N.; Shiga, Takuya; Oshio, Hiroki

Abstract

A mixed-valence heterometallic nonanuclear [3 × 3] grid complex, [CuI2CuII6FeIII(L)6](BF4)5·MeOH·9H2O (1; MeOH = methanol), was synthesized by a one-pot reaction of copper and iron ions with multidentate ligand 2,6-bis[5-(2-pyridinyl)-1H-pyrazol-3-yl]pyridine (H2L). 1 showed five quasi-reversible one-electron redox processes centered at +0.74, +0.60, +0.39, +0.27, and −0.13 V versus SCE, assignable to four CuI/CuII processes and one FeII/FeIII couple, respectively. The two-electron-oxidized species [CuII8FeIII(L)6](PF6)7·4MeOH·7H2O (12eOx), the two-electron-reduced species [CuI4CuII4FeIII(L)6](PF6)3·2H2O (12eRed), and the three-electron-reduced species [CuI4CuII4FeII(L)6](PF6)2·5MeOH·H2O (13eRed) were isolated electrochemically. The four redox isomers were characterized by single-crystal X-ray analysis, SQUID magnetometry, and Mössbauer spectroscopy.

• Journal Article Type: Article
• Acceptance Date: Sep 26, 2023
• Online Publication Date: Oct 13, 2023
• Publication Date: Nov 6, 2023
• Deposit Date: Oct 17, 2023
• Publicly Available Date: Oct 14, 2024
• Journal: Inorganic Chemistry
• Print ISSN: 0020-1669
• Electronic ISSN: 1520-510X
• Publisher: American Chemical Society
• Peer Reviewed: Peer Reviewed
• Volume: 62
• Issue: 44
• Pages: 18003-18008
• DOI: https://doi.org/10.1021/acs.inorgchem.3c02498
• Keywords: Copper, Electrodes, Ions, Molecular structure, Redox reactions
• Public URL: https://nottingham-repository.worktribe.com/output/25956497
• Publisher URL: https://pubs.acs.org/doi/10.1021/acs.inorgchem.3c02498#