Related Experiment Video
Updated: Jun 10, 2026

Reductive Electropolymerization of a Vinyl-containing Poly-pyridyl Complex on Glassy Carbon and Fluorine-doped Tin Oxide Electrodes
Published on: January 30, 2015
How to elucidate and control the redox sequence in vinylbenzoate and vinylpyridine bridged diruthenium complexes
Florian Pevny1, Rainer F Winter, Biprajit Sarkar
1Institut für Anorganische Chemie der Universität Regensburg, Universitätsstrasse 31, D-93040, Regensburg, Germany.
Abstract:
Vinylbenzoate-bridged diruthenium complexes (RHC=CH)(CO)(P(i)Pr(3))(2)Ru(mu-4-OOCC(6)H(4)-CH=CH)RuCl(CO)(P(i)Pr(3))(2) (R = Ph, 3a or CF(3), 3b) and vinylpyridine-bridged (eta(6)-p-cymene)Cl(2)Ru(mu-NC(5)H(4)-4-CH=CH)RuCl(CO)(P(i)Pr(3))(2) (3c) have been prepared from their monoruthenium precursors and investigated with respect to the sequence of the individual redox steps and electron delocalization in their partially and fully oxidized states. Identification of the primary redox sites rests on the trends in redox potentials and the EPR, IR and Vis/NIR signatures of the oxidized radical cations and is correctly reproduced by quantum chemical investigations. Our results indicate that the trifluoropropenyl complex 3b has an inverse FMO level ordering (Ru1-bridge-Ru2 > terminal vinyl-Ru1 site) when compared to its styryl substituted counterpart 3a such that the primary oxidation site in these systems can be tuned by the choice of the terminal alkenyl ligand. It is further shown that the vinylbenzoate bridge is inferior to the vinylpyridine one with regard to charge and spin delocalization at the radical cation level. According to quantum chemical calculations, the doubly oxidized forms of these complexes have triplet diradical ground states and feature two interconnected oxidized vinyl ruthenium subunits.
Related Concept Videos
Benzene to 1,4-Cyclohexadiene: Birch Reduction Mechanism
Diels–Alder Reaction Forming Bridged Bicyclic Products: Stereochemistry
Redox Reactions
Directing Effect of Substituents: meta-Directing Groups
Reactions at the Benzylic Position: Oxidation and Reduction
Directing Effect of Substituents: ortho–para-Directing Groups

![[(DPEPhos)(bcp)Cu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F59739.jpg&w=3840&q=50)