Transition metal oxalate complex

Transition metal oxalate complexes are coordination complexes with oxalate (C₂O₄²⁻) ligands. Some are useful commercially, but the topic has attracted regular scholarly scrutiny. Oxalate (C₂O₄^2-) is a kind of dicarboxylate ligand.^[1] As a small, symmetrical dinegative ion, oxalate commonly forms five-membered MO₂C₂ chelate rings. Mixed ligand complexes are known, e.g., [Co(C₂O₄)(NH₃)₄]^κ+.^[2]

Structures of some metal oxalate complexes

[Cr₂(ox)₅]^4-.
Potassium ferrioxalate (K₃[Fe(C₂O₄)₃]·3H₂O)
Oxaliplatin, an anticancer drug
[Zr(ox)₄]^4-

^ Krishnamurty, Kotra V.; Harris, Gordon M. (1961). "The Chemistry of the Metal Oxalato Complexes". Chemical Reviews. 61 (3): 213–246. doi:10.1021/cr60211a001.
^ Bernal, Ivan; Cetrullo, James (1990). "The phenomenon of conglomerate crystallization. XIX. Clavic dissymmetry in coordination compounds. XVII". Structural Chemistry. 1 (2–3): 235–243. doi:10.1007/BF00674267. S2CID 96021604.

[1] Krishnamurty, Kotra V.; Harris, Gordon M. (1961). "The Chemistry of the Metal Oxalato Complexes". Chemical Reviews. 61 (3): 213–246. doi:10.1021/cr60211a001.

[2] Bernal, Ivan; Cetrullo, James (1990). "The phenomenon of conglomerate crystallization. XIX. Clavic dissymmetry in coordination compounds. XVII". Structural Chemistry. 1 (2–3): 235–243. doi:10.1007/BF00674267. S2CID 96021604.

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