Project/Area Number |
16550037
|
Research Category |
Grant-in-Aid for Scientific Research (C)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Organic chemistry
|
Research Institution | Faculty of Education, Osaka Kyoiku University |
Principal Investigator |
TANI Keita Osaka Kyoiku University, Faculty of Education, Professor, 教育学部, 教授 (60207165)
|
Co-Investigator(Kenkyū-buntansha) |
HIGUCHI Hiroyuki Toyama University, Department of Chemistry, Faculty of Science, Professor, 理学部, 教授 (00165094)
|
Project Period (FY) |
2004 – 2006
|
Project Status |
Completed (Fiscal Year 2006)
|
Budget Amount *help |
¥3,600,000 (Direct Cost: ¥3,600,000)
Fiscal Year 2006: ¥700,000 (Direct Cost: ¥700,000)
Fiscal Year 2005: ¥1,500,000 (Direct Cost: ¥1,500,000)
Fiscal Year 2004: ¥1,400,000 (Direct Cost: ¥1,400,000)
|
Keywords | carbazole / carbazolophane / excimer / exciplex / photoinduced electron transfer / exterplex / fluorescent probe / cyclophane / ドナー-アクセプター / 時間分解EPR / ゼロ磁場分裂 / 電荷分離 / 発光スペクトル |
Research Abstract |
The structure and formation of carbazole (Cz) excimer have been investigated by the help of carbazolopanes, in which two Cz rings are located in face to face orientation and fixed in a distinct geometry. The synthetic methods for [3.n](3,9)carbazolophanes connected with alkylene chain, with cyanamide-or oxa-bridge, 1n and 2n for n = 4, 5, respectively, have been developed. Their structures have been conclusively characterized by ^1H NMR and X-ray analyses. It has been revealed that two Cz rings are taken to be partially overlapped geometry. Absorption spectra of 1n and 2n indicate that the existence of transannular π-π electronic interaction. Fluorescence spectra of 1n and 2n are mirror image of absorption spectra, which show that their fluorescence is monomer-like emission. From these results, the structure of a partially overlapped conformation taken for 1n and 2n (n = 4, 5) is not enough for excimer emission, but may require an appropriate conformation such as close contact or parallel orientation of carbazole rings. As exciplex formation between Cz and acceptor such as terephthalate (TP) was reported, Cz-terephthalate cyclophane (Cz-TP) is synthesized. The structure of Cz-TP has been characterized by NMR and X-ray analysis. The peak wavelengths of the emission in the fluorescence spectra are shifted to a longer wavelength with increases in the dielectric constant of solvents. The polarity dependence of the exciplex emission of Cz-TP is well described by the Lippert-Mataga relation over wide polarity and temperature ranges. Therefore, Cz-TP is a useful polarity probe for the evaluation of local polarity in both liquid and solid phase including polymers. Carbazolophane-terephthalate triads have also synthesized, whose emission behavior change from excimer to exterplex with increases in the polarity of solvents. It has turned out that photoinduced electron transfer has occurred in MeCN.
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