Square-planar complexes photooxidation

Photooxidation of coordinated oxalate has been known since the earliest studies of transition metal photochemistry (42). In these reactions oxalate ligand is photooxidized to CO2, and up to two metal centers are reduced by one electron (e.g. ferrioxalate). We wondered whether the oxalate ligand could be a two-electron photoreductant, by simultaneous or rapid sequential electron transfer, with metals prone to 2e redox processes. Application of this concept to l6e square planar d complexes, Equation 15, was attractive because it should produce solvated I4e metal complexes that are inorganic analogues of... 

Photochemical oxidation of square-planar bis(l,2-dithiolene) complexes of Ni, Pd, and Pt is by no means limited to IPCT excitation. Photooxidation also occurs in halocarbon solvents. In 1982, two separate reports addressed the photochemistry of metal bis(l,2-dithiolene) complexes. Vogler and Kunkely (80) investigated complexes of the type M(S2C2R-2)2, where M = Ni, Pd, Pt,... 

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