The synthesis and the reactivity of arene ruthenium oxalato complexes

Abstract

This article outlines the reactions of the well known [RuCl(η⁶-p-cymene)]₂(μ-η⁴-C₂O₄) and [RuCl(η⁶-p-cymene)(η²-dppm)][PF₆] ruthenium complexes with C₂O₄(Me₄N)₂ in the mol ratios 1:1 and 2:1. While the 2:1 ratio reaction led to the sole and expected binuclear product {[Ru(η⁶-p-cymene)(η²-dppm)]₂(μ-η²-C₂O₄)}[PF₆]₂, the reaction also afforded the unexpected mononuclear complex [RuCl(η²-C₂O₄)(η⁶-p-cymene)][Me₄N]. This can also be obtained in improved yield by reacting [RuCl₂(p-cymene)]₂ with C₂O₄[Me₄N]₂ in a 1:1 mol ratio. Surprisingly, when [RuCl(η⁶-p-cymene)]₂(μ-η⁴-C₂O₄) was reacted with an equimolar amount of the ligand dppm, the expected complex {[Ru(η⁶-p-cymene)]₂(μ-η⁴-C₂O₄)(μ-dppm)}[PF₆]₂ was accompanied by [RuCl(η⁶-p-cymene)(η²-dppm)][PF₆] in an inseparable solid mixture.

KEY WORDS: Ruthenium, Arene, p-cymene, Mesitylene, Oxalate, bis-(Dipenylphosphino)methane

Bull. Chem. Soc. Ethiop. 2008, 22(2), 207-217.