1586038-68-7Relevant academic research and scientific papers
Tuning reductive and oxidative photoinduced electron transfer in amide-linked anthraquinone-porphyrin-ferrocene architectures
Melomedov, Jascha,Ochsmann, Julian Robert,Meister, Michael,Laquai, Frédéric,Heinze, Katja
, p. 1984 - 2001 (2014)
Porphyrin amino acids 3a-3h with meso substituents Ar of tunable electron-donating power (Ar = 4-C6H4OnBu, 4-C6H4OMe, 4-C6H4Me, Mes, C6H5, 4-C6H4F, 4-C6H4CF3, C6F5) have been linked at the N terminus to anthraquinone Q as electron acceptor through amide bonds to give Q-PAr dyads 4a-4h. These were conjugated to ferrocene Fc at the C terminus as electron donor to give the acceptor-chromophore-donor Q-PAr-Fc triads 6a-6h. To further modify the energies of the electronically excited and charge-separated states, the triads 6a-6h were metallated with zinc(II) to give the corresponding Q-(Zn)PAr-Fc triads Zn-6a-Zn-6h. The Q-PAr1 dyad (Ar1 = C6H5) was further extended with a second porphyrin PAr2 (Ar2 = 4-C6H4Me) as well as appended to a ferrocene to give the tetrad Q-PAr1-PAr2-Fc 9. Almost all the conjugates show strongly reduced fluorescence quantum yields and excited-state lifetimes, which has been interpreted as photoinduced electron transfer (PET) either from the excited porphyrin to the quinone (oxidative PET) or from the ferrocene to the excited porphyrin (reductive PET). Electrochemical data, absorption spectroscopy, steady-state emission, time-resolved fluorescence, transient absorption pump-probe spectroscopy as well as DFT calculations have been used to elaborate the preferred PET pathway (reductive vs. oxidative PET) in these architectures with systematically varied electron-donating substituents at the central chromophore. The initial photoinduced electron transfer (PET) in anthraquinone-(porphyrinAr)n-ferrocenes (n = 1, 2) is modulated by the HOMO and LUMO levels of the porphyrin chromophores by meso substituent effects. Electrochemical and spectroscopic data as well as DFT calculations were used to elaborate the preferred PET pathway in these architectures with different electron donation on the porphyrin.
Tuning reductive and oxidative photoinduced electron transfer in amide-linked anthraquinone-porphyrin-ferrocene architectures
Melomedov, Jascha,Ochsmann, Julian Robert,Meister, Michael,Laquai, Frédéric,Heinze, Katja
supporting information, p. 1984 - 2001 (2014/05/06)
Porphyrin amino acids 3a-3h with meso substituents Ar of tunable electron-donating power (Ar = 4-C6H4OnBu, 4-C 6H4OMe, 4-C6H4Me, Mes, C 6H5, 4-C6H4F, 4-C6H 4CF3, C6F5) have been linked at the N terminus to anthraquinone Q as electron acceptor through amide bonds to give Q-PAr dyads 4a-4h. These were conjugated to ferrocene Fc at the C terminus as electron donor to give the acceptor-chromophore-donor Q-P Ar-Fc triads 6a-6h. To further modify the energies of the electronically excited and charge-separated states, the triads 6a-6h were metallated with zinc(II) to give the corresponding Q-(Zn)PAr-Fc triads Zn-6a-Zn-6h. The Q-PAr1 dyad (Ar1 = C 6H5) was further extended with a second porphyrin P Ar2 (Ar2 = 4-C6H4Me) as well as appended to a ferrocene to give the tetrad Q-PAr1-PAr2-Fc 9. Almost all the conjugates show strongly reduced fluorescence quantum yields and excited-state lifetimes, which has been interpreted as photoinduced electron transfer (PET) either from the excited porphyrin to the quinone (oxidative PET) or from the ferrocene to the excited porphyrin (reductive PET). Electrochemical data, absorption spectroscopy, steady-state emission, time-resolved fluorescence, transient absorption pump-probe spectroscopy as well as DFT calculations have been used to elaborate the preferred PET pathway (reductive vs. oxidative PET) in these architectures with systematically varied electron-donating substituents at the central chromophore. Copyright
