| Abstract
| - Di(2-pyridyl)methanesulfonato hydroxo platinum(II) ethylene complex 4b, LPtII(C2H4)OH, reacts readilywith oxygen in aqueous solution to cleanly produce unsymmetrical 2-hydroxyethyl platinum(IV) complexunsym-6b, LPtIV(C2H4OH)(OH)2. The latter eliminates ethylene oxide and ethylene glycol in virtuallyquantitative yield in neutral aqueous solution at 80 °C and produces the dinuclear μ-hydroxo platinum(II) complex 7 as another reaction product. The oxidation reaction was shown to proceed via an anionic2-hydroxyethyl hydroxo platinum(II) intermediate, 5b. The chloro analogues 4a and 5a are inert towarddioxygen but can be converted to 6b under air in the presence of 1 equiv of NaOH. As established byDFT calculations, both the formal charge on the platinum(II) center and the nature of ligands coordinatedto it have a crucial effect on the energy of the HOMO of the complexes, which may be related to theirability to undergo an aerobic oxidation.
- Facile aerobic oxidation of di(2-pyridyl)methanesulfonato hydroxo platinum(II) ethylene complex LPtII(C2H4)OH in aqueous solution cleanly produces 2-hydroxyethyl dihydroxo platinum(IV) complex LPtIV(C2H4OH)(OH)2. The latter eliminates ethylene oxide and ethylene glycol in high yield in neutral aqueous solution at 80 °C.
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