論文

査読有り
2007年3月

The effect of meta-substitution on the photochemical properties of benzoxazole derivatives

BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN
  • Asuka Ohshima
  • ,
  • Masashi Ikegami
  • ,
  • Yoshihiro Shinohara
  • ,
  • Atsuya Momotake
  • ,
  • Tatsuo Arai

80
3
開始ページ
561
終了ページ
566
記述言語
英語
掲載種別
研究論文(学術雑誌)
DOI
10.1246/bcsj.80.561
出版者・発行元
CHEMICAL SOC JAPAN

The photochemistry of 2-(2-hydroxy-3-methoxyphenyl)benzoxazole (3-MHBO) and 2-(2-hydroxy-4-methoxyphenyl)benzoxazole (4-MHBO) have been investigated. The excited-state properties of 4-MHBO were similar to those for the parent compound 2-(2-hydroxyphenyl)benzoxazole (HBO), whereas different properties were observed for 3-MHBO. 4-MHBO in benzene exhibited large Stokes-shifted fluorescence from the keto-form in the excited singlet state (K-E*) after excited-state intramolecular proton transfer (ESIPT), whereas 3-MHBO emitted dual fluorescence from E* and K-E* species. Fluorescence due to K-E* for 3-MHBO (lambda(max) = 525 nm) occurred at a considerably longer wavelength than that of 4-MHBO (lambda(max) = 480 nm). The fluorescence efficiency of 3-MHBO (Phi(f) = 0.002) was much smaller than those of 4-MHBO and HBO (Phi(f) = 0.0 18 and 0.02, respectively). These results are consistent with suppression of ESIPT, stabilization of K-E* species, and acceleration of non-radiative decay, probably because of the formation of a hydrogen bond between phenol oxygen and methoxy hydrogen at 3-position in 3-MHBO. Thus, 3-MHBO displayed a meta-substituent effect involving the relaxation pathway of excited state HBO derivatives.

Web of Science ® 被引用回数 : 17

リンク情報
DOI
https://doi.org/10.1246/bcsj.80.561
Web of Science
https://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=JSTA_CEL&SrcApp=J_Gate_JST&DestLinkType=FullRecord&KeyUT=WOS:000245885000020&DestApp=WOS_CPL
ID情報
  • DOI : 10.1246/bcsj.80.561
  • ISSN : 0009-2673
  • eISSN : 1348-0634
  • Web of Science ID : WOS:000245885000020

エクスポート
BibTeX RIS