A Ruthenium Bridge in Fullerene–Ferrocene Arrays: Synthesis of [Ru(C60Me5)R(CO)2] (R=C6H4Fc, C≡CFc) and Their Charge‐Transfer Properties

Abstract New fullerene–ferrocene arrays, [Ru(C 60 Me 5 )(C 4 H 6 Fc)(CO) 2 ] (Fc=ferrocenyl) and [Ru(C 60 Me 5 )(CCFc)(CO) 2 ], in which the ruthenium complex functions as a conjugative bridge, were synthesized by the reaction of [Ru(C 60 Me 5 )Cl(CO) 2 ] with FcC 6 H 4 MgBr and FcCCLi, respectively. These compounds were investigated by electrochemical measurement, single‐crystal X‐ray structural analysis, and photophysical measurement. Upon photoirradiation, the former compound was converted rapidly into the corresponding triplet state in toluene ( τ singlet =21 ps), whereas the charge‐separated state was predominant in THF ( τ singlet =10.5 ps; τ CS =355 ps). The latter compound, on the other hand, formed the charge‐separated state in both toluene and THF ( τ singlet =3.0 ps; τ CS =152 ps). Thus, the structural difference between the phenylene and acetylene bridges in 1 and 2 , respectively, was found to change the outcome of the photophysical processes.