Efficient Light Activation of a [Ru(bpy)(tpy)Cl]+ Catalyst by a Porphyrin Photosensitizer at Small Driving Force

Light activation of dyads containing porphyrins and a catalytic ruthenium complex having a high oxidation potential (~1 V vs SCE) is investigated by time-resolved spectroscopy. It is shown that activation of the ruthenium complex occurs through oxidative quenching of the chromophore in the presence of a reversible electron acceptor. Despite the lack of driving force for intramolecular electron transfer, an efficient intramolecular oxidation of the catalyst is observed, suggesting that porphyrins are attractive chromophores to activate oxidation catalysts throughout the visible spectrum.