Heterometallic complexes containing 1,1′-(CC)2Fc′ units linking two different metal centres

Abstract Proto-desilylation of 1-(Me 3 SiC C)-1′-{Cp ∗ (dppe)RuC C}Fc′ ( 1 ) afforded the corresponding ethynyl derivative 2 , from which the green Co 2 (μ-dppm) n (CO) 8−2 n ( n  = 0, 1) adducts 3 and 4 were obtained. Replacement of the ethynyl proton in reactions between 2 and AuCl(PPh 3 ), Hg(OAc) 2 or FeCl(dppe)Cp ∗ gave complexes 1-(RC C)-1′-{Cp ∗ (dppe)RuC C}Fc′ [R = Au(PPh 3 ) 5 , 1/2Hg 6 , Fe(dppe)Cp ∗ 8 ]; the latter gave bis-vinylidene 9 with MeI, characterised (as was 2 ) by a single crystal X-ray study. Oxidative coupling of 2 (CuCl/tmeda/acetone, air) gave diyne 10 , while coupling of 5 with Co 3 (μ 3 -CBr)(μ-dppm)(CO) 7 afforded 1-{Cp ∗ (dppe)RuC C}-1′-{(OC) 7 (μ-dppm)Co 3 (μ 3 -CC C)}Fc′ ( 11 ). Cyclic voltammetric measurements indicated that there was no significant electronic coupling between the end-groups through the ferrocene centre in any of these compounds.