Trimetallic complexes containing 1,1′-Rc′(CC)2 units [Rc′ = ruthenocene-1,1′-diyl, Ru(η-C5H4–)2]

Reactions between 1,1′-(Me 3 SiC C) 2 Rc′ [Rc′ = ruthenocen-1,1′-diyl, Ru(η-C 5 H 4 –) 2 ] and RuCl(PP)Cp′ in the presence of KF gave 1,1′-{Cp(PP)RuC C} 2 Rc′ [Cp′ = Cp, PP = PPh 3 1 , P( m -tol) 3 2 , dppe 3 , dppf 4 ; Cp′ = Cp ∗ , PP = dppe 5 ]. Compounds 1 and 2 react with tcne to give two diastereomers a / b of the allylic (vinylcarbene) complexes 6 and 7 , while methylation of 5 gave the bis-vinylidene [1,1′-{Cp ∗ (dppe)Ru C CMe} 2 Rc′](BPh 4 ) 2 ( 8 ). The X-ray structures of 4 , 6b and 8 have been determined. Cyclic voltammograms indicate that there is some electronic communication between the ruthenium end-groups through the Rc′ centre.