TY - JOUR
T1 - Dynamics of photoinduced electron transfer in a carotenoid - porphyrin - dinitronaphthalenedicarboximide molecular triad
AU - Tan, Quan
AU - Kuciauskas, Darius
AU - Lin, Su
AU - Stone, Simon
AU - Moore, Ana
AU - Moore, Thomas
AU - Gust, Devens
PY - 1997/6/26
Y1 - 1997/6/26
N2 - An electron acceptor moiety based on the 4,5-dinitro-1,8-naphthalenedicarboximide system has been prepared and used as the basis for synthesis of a porphyrin - imide dyad (P-NIm) and a carotenoid - porphyrin - imide triad molecule (C-P-NIm). Excitation of the porphyrin moiety in either compound with visible light leads to rapid photoinduced electron transfer to generate in high yield a charge-separated state consisting of the porphyrin radical cation and imide radical anion. In the triad, this C-P•+-NIm•- state decays in part by a second electron transfer from the carotenoid to yield a final C•+-P-NIm•- charge-separated state. In benzonitrile, this state is formed with a quantum yield of 0.33 and has a lifetime of 430 ns. The 4,5-dinitro1,8-naphthalenedicarboximide moiety is conveniently synthesized and undergoes facile and reversible one-electron reduction. The NIm•- ion has a readily observable spectroscopic signature in the visible. In contrast to a series of closely related triads reported by other investigators, the triad studied here shows no evidence for photoinduced electron transfer from the carotenoid first excited singlet state.
AB - An electron acceptor moiety based on the 4,5-dinitro-1,8-naphthalenedicarboximide system has been prepared and used as the basis for synthesis of a porphyrin - imide dyad (P-NIm) and a carotenoid - porphyrin - imide triad molecule (C-P-NIm). Excitation of the porphyrin moiety in either compound with visible light leads to rapid photoinduced electron transfer to generate in high yield a charge-separated state consisting of the porphyrin radical cation and imide radical anion. In the triad, this C-P•+-NIm•- state decays in part by a second electron transfer from the carotenoid to yield a final C•+-P-NIm•- charge-separated state. In benzonitrile, this state is formed with a quantum yield of 0.33 and has a lifetime of 430 ns. The 4,5-dinitro1,8-naphthalenedicarboximide moiety is conveniently synthesized and undergoes facile and reversible one-electron reduction. The NIm•- ion has a readily observable spectroscopic signature in the visible. In contrast to a series of closely related triads reported by other investigators, the triad studied here shows no evidence for photoinduced electron transfer from the carotenoid first excited singlet state.
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U2 - 10.1021/jp970682l
DO - 10.1021/jp970682l
M3 - Article
AN - SCOPUS:0031167554
SN - 1520-6106
VL - 101
SP - 5214
EP - 5223
JO - Journal of Physical Chemistry B
JF - Journal of Physical Chemistry B
IS - 26
ER -