Ruthenium aryloxides

The addition of 4-methylphenol to the ruthenium species [Ru(>j -Me2P-CH2)(Me) Me3)4] produces the cyclometallated aryloxide [Ru(0- / -C6H4)(PMe3)4]. Reaction with CO and CO2 was found to lead to insertion into the metal-aryl bond to produce five- and six-membered metallacycles respectively. ... 

Ruthenium chemistry typically finds aryloxide ligands attached to the metal in low oxidation states. The extensive number of carbonyl aryloxide compounds reported for this metal exemplifies this (Table 6.34). The cluster compound [(H)2Ru6(CO)i6(M2-0-f -C6H4)] and derivatives contain the metallated phenoxide bridging two metal centres as well as -bound to another. 

Figure 12.7 Ruthenium complexes with increased rigidity of the chelate ring (31, 32), and fluoro aryloxide anionic ligands (33-35).

As a result, the pyridine ligand is more labile in complex 16 and 17 than in 15 resulting in higher metathesis activity. It must be noted that the presence of the aryloxide ligands increased the affinity of these complexes for silica thus allowing an efficient removal of ruthenium contaminants by a single column chromatography purification. 

Keywords Ruthenium, eatalysis, aryloxide, pseudohalide, metathesis, activity, electronics. 

Hartwig JF, Bergman RG, Andersen RA (1991) Insertion reactions of CO and CO2 with ruthenium benzyl, arylamido, and aryloxide complexes a comparison of the reactivity of ruthenium-carbon, ruthenium-nitrogen, and ruthenium-oxygen bonds. J Am Chem Soc 113 6499-6508... 

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