Diruthenium Complexes of Axial Ferrocenyl−Polyynyl Ligands: The Cases of C₆Fc and C₈Fc

Four Ru2(Y-DMBA)4(C2nFc)2 type compounds with n = 3, 4 and Y-DMBA = N,N’-dimethylbenzamidinate, N,N’-dimethyl-3-methoxybenzamidinate were prepared using a weak-base protocol and characterized using voltammetry and single-crystal X-ray diffraction. Structural studies yielded Fc−Fc (edge−edge) separations of 22.0 and 27.1 Å for n = 3, 4, respectively. The potential differences between two Fc oxidation couples were determined via voltammetric studies as 0.24 and 0.22 V for n = 3, 4, respectively, implying the retention of strong interferrocene electronic couplings over extended distances.