TOWARD PHOTOCHEMICAL CARBON-DIOXIDE ACTIVATION BY TRANSITION-METAL COMPLEXES

Nickel and cobalt complexes of 14-membered tetraazamacrocycles mediate electron transfer and produce CO in the photochemical reduction of CO 2. Two integrated systems for the CO2 reduction are discussed: (1) pho tophysical properties of bifunctional supramolecules, Ru(bpy)2(bpy-L10 M)4+ (bpy = 2,2'-bipyridine, bpy-L10 = din-6-ylmethyl)-1,4,8,11-tetraa zacyclotetradecane, M = H-2, Ni) and its limitation as a photocatalyst ; (2) advantages of multimolecular system with p-terphenyl as a photos ensitizer, a cobalt macrocycle as an electron mediator, and a tertiary amine as a sacrificial electron donor.