TY - JOUR
T1 - Synthesis and electronic and photophysical properties of [2.2]- and [3.3]paracyclophane-based donor-donor′-acceptor triads
AU - Miyazaki, Takaaki
AU - Shibahara, Masahiko
AU - Fujishige, Jun Ichi
AU - Watanabe, Motonori
AU - Goto, Kenta
AU - Shinmyozu, Teruo
N1 - Publisher Copyright:
© 2014 American Chemical Society.
PY - 2014/12/5
Y1 - 2014/12/5
N2 - Three types of the donor(D)-donor′(D′)-acceptor(A) triads 1-6 with different D-A combinations, carbazole (Cz, D)-[n.n]PCP(D′)-1,8-naphthalimide (NI, A) (1-3), 10H-phenothiazine (PTZ, D)-[n.n]PCP(D′)-NI(A) (4, 5), and 10-methyl-10H-phenothiazine (Me-PTZ, D)-[2.2]PCP-2,1,3-benzothiadiazole (BTD, A) 6, were synthesized for the elucidation of their photophysical properties. The absorption spectra and electrochemical properties indicated that the chromophores (D, D′, and A) do not interact with each other in the ground state. Cz-(CH2)3-[2.2]PCP-(CH2)3-NI 1 and Cz-(CH2)3-[3.3]PCP-(CH2)3-NI 2 show an exciplex emission between the PCP and NI moieties in cyclohexane and the intensity of the band is much higher in 2 than in 1, whereas Cz-(CH2)2-[2.2]PCP-(CH2)2-NI 3 does not show any exciplex emission in cyclohexane. These results indicated that the combination of [3.3]PCP and a trimethylene chain is preferable for the exciplex formation. PTZ-(CH2)3-[2.2]PCP-(CH2)3-NI 4 shows a broad band at 519 nm in cyclohexane, which is associated with the formation of the exterplex band among the NI, [2.2]PCP, and PTZ moieties, while PTZ-(CH2)3-[3.3]PCP-(CH2)3-NI 5 does not show the band. Me-PTZ-(CH2)2-[2.2]PCP-(CH2)2-BTD 6 shows a broad fluorescence band due to both the BTD and PTZ moieties in cyclohexane. In CH3CN, the fluorescence spectra of 1-6 suggest the presence of a photoinduced charge separation process. The study of the photoinduced charge separation process will be soon reported elsewhere.
AB - Three types of the donor(D)-donor′(D′)-acceptor(A) triads 1-6 with different D-A combinations, carbazole (Cz, D)-[n.n]PCP(D′)-1,8-naphthalimide (NI, A) (1-3), 10H-phenothiazine (PTZ, D)-[n.n]PCP(D′)-NI(A) (4, 5), and 10-methyl-10H-phenothiazine (Me-PTZ, D)-[2.2]PCP-2,1,3-benzothiadiazole (BTD, A) 6, were synthesized for the elucidation of their photophysical properties. The absorption spectra and electrochemical properties indicated that the chromophores (D, D′, and A) do not interact with each other in the ground state. Cz-(CH2)3-[2.2]PCP-(CH2)3-NI 1 and Cz-(CH2)3-[3.3]PCP-(CH2)3-NI 2 show an exciplex emission between the PCP and NI moieties in cyclohexane and the intensity of the band is much higher in 2 than in 1, whereas Cz-(CH2)2-[2.2]PCP-(CH2)2-NI 3 does not show any exciplex emission in cyclohexane. These results indicated that the combination of [3.3]PCP and a trimethylene chain is preferable for the exciplex formation. PTZ-(CH2)3-[2.2]PCP-(CH2)3-NI 4 shows a broad band at 519 nm in cyclohexane, which is associated with the formation of the exterplex band among the NI, [2.2]PCP, and PTZ moieties, while PTZ-(CH2)3-[3.3]PCP-(CH2)3-NI 5 does not show the band. Me-PTZ-(CH2)2-[2.2]PCP-(CH2)2-BTD 6 shows a broad fluorescence band due to both the BTD and PTZ moieties in cyclohexane. In CH3CN, the fluorescence spectra of 1-6 suggest the presence of a photoinduced charge separation process. The study of the photoinduced charge separation process will be soon reported elsewhere.
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U2 - 10.1021/jo5020273
DO - 10.1021/jo5020273
M3 - Article
AN - SCOPUS:84916225038
SN - 0022-3263
VL - 79
SP - 11440
EP - 11453
JO - Journal of Organic Chemistry
JF - Journal of Organic Chemistry
IS - 23
ER -