Bis[(μ‐iodo)iodo‐η‐cyclopentadienylruthenium(III)], ‘CpRuI 2 ’ = [CpRuI 2 ] 2 : a Further Example of a [CpXM(μ‐X) 2 MXCp] Parent with cis Arrangement

The very limited array of (structurally described) adducts of the form [CpMX 2 ] 2 ≡ [CpMX(μ‐X) 2 MXCp] with the unsubstituted/parent Cp (≡ C 5 H 5 , cyclopentadienyl) ligand is augmented by a study of [CpIRu(μ‐I) 2 RuICp], found to be isotypic with the recently described chloride and, with it, providing the only examples of such dimers in their ‘ cis ’ form, i.e ., the terminal‐X and Cp pairs to the same side of the Ru 2 (μ‐X) 2 arrays, which are appreciably folded at the X···X lines, with the short Ru···Ru distances (2.7748(6) (X = Cl), 2.9034(8) Å (X = I)), consistent with the presence of appreciable metal‐metal bonding ( cf. the M = Cr, X = Cl counterpart which is trans , Cr···Cr 3.3447(8) Å).