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Updated: May 15, 2026

Experimental Approaches for the Synthesis of Low-Valent Metal-Organic Frameworks from Multitopic Phosphine Linkers
Published on: May 12, 2023
Metal-metal bonding in low-coordinate dicobalt complexes supported by phosphinoamide ligands
Ramyaa Mathialagan1, Subramaniam Kuppuswamy, Alexandra T De Denko
1Department of Chemistry, Brandeis University, 415 South Street, Waltham, Massachusetts 02451, United States.
Abstract:
Homobimetallic dicobalt complexes featuring metal centers in different coordination environments have been synthesized, and their multielectron redox chemistry has been investigated. Treatment of CoX(2) with MesNKP(i)Pr(2) leads to self-assembly of [(THF)Co(MesNP(i)Pr(2))(2)(μ-X)CoX] [X = Cl (1), I (2)], with one Co center bound to two amide donors and the other bound to two phosphine donors. Upon two-electron reduction, a ligand rearrangement occurs to generate the symmetric species (PMe(3))Co(MesNP(i)Pr(2))(2)Co(PMe(3)) (3), where each Co has an identical mixed P/N donor set. One-electron oxidation of 3 to generate a mixed valence species promotes a ligand reararrangement back to an asymmetric configuration in [(THF)Co(MesNP(i)Pr(2))(2)Co(PMe(3))][PF(6)] (4). Complexes 1-4 have been structurally characterized, and their metal-metal interactions are discussed in the context of computational results.
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