CpRu Alkoxides with σ-Bridging Phenoxo Groups. X-ray Structure of [CpRu(μ-OMe)(μ-OC6H3-2,4-(t-Bu)2)]

[Cp*RuOMe]2 (1) reacts with phenols by successive exchange of one and two OMe groups for the phenolato group, forming mixed μ-methoxy−μ-phenolato complexes (5) and bis(μ-phenolato) dimeric complexes (6) successively. The latter, by an intramolecular rearrangement, convert into Cp*Ru(η5-oxocyclohexadienyl) complexes (7). With phenol and 2-methyl-5-isopropylphenol (carvacrol) the stepwise reactions were followed by NMR spectroscopy. Using 2,4-di-tert-butylphenol, both the mono(phenolato) (5c) and bis(phenolato) (6c) complexes have been isolated. The latter complex is obtained best from Cp*Ru(proline) (8) and 1. Complex 5c was characterized by an X-ray structure. The molecular geometry is very similar to the one found for 1.