Synthesis and charge delocalization property of multimetallic molecular wires with diethynylthiophene bridges

Here we report properties of thiophene-rich, acetylide-type mono-, di- and tri-nuclear ruthenium molecular wires 1-4, which are prepared by rationally designed coupling of vinylidene intermediates. Electrochemical analysis of 1-3 reveals fully reversible redox waves, the numbers of which are equal to those of the ruthenium fragments. Spectroelectrochemical analysis of 2 and 3 reveals the clear step-bystep oxidation processes. Analysis of NIR absorption bands reveals that the monocationic species 2+ and 3+ are highly charge-delocalized species, which are further supported by DFT and TD-DFT calculations of their model complexes. (C) 2017 Elsevier B.V. All rights reserved.