Bimetallic Ruthenium Complexes: Synthesis, Characterization, and the Effect of Appending Long Carbon Chains to Their Bridges

Abstract

A series of binuclear ruthenium complexes [RuCl(CO)(PMe 3 ) 3 ] 2 (μ-CH═CH−Ar−CH═CH) (Ar = C 6 H 2 (OR) 2 -2,5; R = CH 3 ( 4a ), n C 4 H 9 ( 4b ), n C 6 H 13 ( 4c ), n C 8 H 17 ( 4d ), n C 10 H 21 ( 4e ), n C 12 H 25 ( 4f ), n C 14 H 29 ( 4g )), [RuCl(CO)(PMe 3 ) 3 ] 2 (μ-CH═CH−Ar−≡−Ar−CH═CH) (Ar = C 6 H 2 (R) 2 -2,5; R = OCH 3 ( 10a ), O n C 8 H 17 ( 10b ), H ( 10c )), and [RuCl(CO)(PMe 3 ) 3 ] 2 (μ-CH═CH−Ar−≡−Ar−≡−Ar−CH═CH) (Ar = C 6 H 2 (R) 2 -2,5; R = OCH 3 ( 13a ), O n C 8 H 17 ( 13b ), H ( 13c )) have been synthesized. These complexes have been characterized by elemental analysis, NMR, and UV/vis spectrophotometry. The structures of 4b and 4d have been determined by X-ray crystallography. Electrochemical studies have shown that long carbon chains attached to the bridges of the complexes facilitate the stability of mixed-valence bimetallic ruthenium complexes.