Vinyl-ruthenium entities as markers for intramolecular electron transfer processes

The present aCCOlll1t summari zes our work on mononuclear vinyl ruthenium complexes of the type RuCI (CH=CHR')(CO)(PR,h L, elivinyl brielgeel eliruthenium comp lexes (RuCl(CO)(PR3hLh(fl CH=CH bridge CH= CH) ami on heterobinuclear syste ms wh e re only one of the two redox active metal organic moieti es is of the vinyl ruthenium type. The favourabl e electroche mical prope rties of th e (RuCl (CO)(PR 3 h L(CH= CH) tag and the va ri ous spectroscopi c handles offered by th a t unit provid e detai led in sights into the charge and spin delocalization over the (MCI(CO)(PR3 h L) and CH= CHR' constituents in their associated radical cations. They also offer a conven ient mean s 1'01' measuring e lectron ic couplin g in the mixed va le nt radi ca l cations of the homo anel heterodinucl ea r vinyl brid ged cOlllplexes a nel, lll1der favourable circumsta nces, on the rate of intralllol ecular electron transfe r betw ee n the individual redox sites. As pects of thi s work include examples of compl exes showing tim e de pendent valence trap ping, comp lexes aimed at elelin eating the efficiencies of throu gh space versus through bonel pathways for elec tron delocalization, complexes where electrostatic effects on the redox splitting t!.E'12 domina te ove r those from the reso nance contribu tioll and systems that exhibit exte nsive charge and spin delocali za tion betwee n two di slike endgroups despite their intrin sically differe nt re