Oxidation of olefins catalysed by (HEDTA) Ru^v=O

Abstract

The complex K[Ru^III(HEDTA)Cl].H₂O 1̲ and [(HEDTA) Ru^v=O] 2̲ were prepared and characterised by elemental analysis, IR, UV-Vis spectroscopy, conductivity, magnetic susceptibility and electrochemical studies (HEDTA-hydroxyethyl-ethylenediaminetriacetate anion). The kinetics of oxygen atom transfer of [Ru^III(HEDTA) (H₂O)]1a̲ to [(HEDTA) Ru^v=O] 2̲ with iodosoylbenzene was studied spectrophotometrically by using stopped-flow technique. The oxygen atom transfer from complex 2̲ to cyclohexene, cyclooctene, styrene, cis andtrans-stilbene was studied by the disappearance of the characteristic oxo peak (λ_max=391 nm) at constant pH (3.0) and ionic strength (μ=0.1 M NaClO₄) and also product analysis by gas chromatography (GC). The activation parameters for both the oxygenation of complex1 to complex 2̲, and oxygen atom transfer from complex 2̲ to the organic substrates studied were evaluated and suitable mechanisms proposed.