Synthesis of a Ferrocenyl-Capped Ruthenium(II) Bis(acetylide) Complex:  A Model for Organometallic Molecular Wires

trans -Ru(dppm) 2 (C⋮CFc) 2 ( 1, dppm = Ph 2 PCH 2 PPh 2, Fc = ferrocenyl) was prepared by the CuI-catalyzed coupling of FcC⋮CSn( n -Bu) 3 with cis -RuCl 2 (dppm) 2 . We have demonstrated by cyclic voltammetry that the ruthenium(II) bis(acetylide) bridge, −C⋮C−Ru(dppm) 2 −C⋮C−, of 1 enhances the ground-state electronic communication between terminal ferrocenyl groups compared to the all-carbon butadiynyl bridge of 1,4-diferrocenylbutadiyne, Fc−C⋮C−C⋮C−Fc.