Synthesis, structure and reactivities of the dinuclear μ-η1:η6-arylethynyl ruthenium complexes [Cp(PR3)2Ru(μ-η1:η6-CCC6H4Me-p)RuCp*]·Cl (R=Ph, Me; Cp=η5-C5H5, Cp*=η5-C5Me5). The molecular structure of [Cp(PPh3)2Ru(μ-η1:η6-CCC6H4Me-p)RuCp*]·PF6

Treatment of [Cp(PR3)2Ru(CCC6H4Me-p) (1a, R=Ph 1b, R=Me; Cp=η5-C5H5) with [Cp*Ru(μ3·Cl)]4 (Cp*=η5-C5Me5) selectively produced the novel dinuclear μ-η1:η6- arylethynyl complex Cp(PR3)2Ru(μ-η1:η6-CCC6H4Me-p)RuCp*] (2·Cl: 2a, R=Ph; 2b, R=Me). Protonation of 2·OTf (OTf=OSO2CF3) by TfOH afforded the corresponding vinylidene complex [Cp(PR3)2Ru(μ-η1:η6-CCHC6H4Me-p)RuCp*]·[OTf]2 (3·[OTf]2: 3a, R=Ph; 3b, R=Me), which regenerated 2·OTf upon treatment with LiBHEt3. Reaction of 2a·Cl with I2 and subsequent anion metathesis with AgBF4 produced the iodovinylidene complex [Cp(PPh3)2Ru(μ-η1:η6-CCIC6H4Me-p)RuCp*]·[BF4]2 (4·[BF4]2), whereas similar treatment of 2b·PF6 yielded the iodo/arylethynyl complex [Cp(I)(PMe3)2Ru(μ-η1:η6-CCC6H4Me-p)RuCp*]·[PF6]2 (5·[PF6]2). Substitution of one of the PPh3 ligands in 2a·OTf proceeded under 1 atm of CO to form [Cp(PPh3)(CO)Ru(μ-η1:η6-CCC6H4Me-p)RuCp*]·OTf (6·OTf). The molecular structure of 2a·PF6 was determined by X-ray crystallography.