Photochemical generation of cyclopentadienyliron dicarbonyl anion by a nicotinamide adenine dinucleotide dimer analogue

Irradiation of the absorption band of an NAD (nicotinamide adenine dinucleo tide) dimer analogue, 1-benzyl-1,4-dihydronicotinamide dimer, (BNA)(2), in acetonitrile containing a cyclopentadienyliron dicarbonyl dimer, [CpFe(CO)( 2)](-), results in generation of 2 equiv of the cyclopentadienyliron dicarb onyl anion, [CpFe(CO)(2)](-), accompanied by the oxidation of (BNA)(2) to y ield 2 equiv of BNA(+). The studies on the quantum yields, the electrochemi stry, and the transient absorption spectra have revealed that the photochem ical generation of [CpFe(CO)(2)](-) by (BNA)(2) proceeds via photoinduced e lectron transfer from the triplet excited state of (BNA)(2) to CCpFe(CO)(2) ](2).