Substituent effects on the photochromic properties of benzothiophene-based derivatives.
Five diarylethene photochromic derivatives, the structures of which incorporate a central benzothiophene unit, a left-hand thiazole group, and a right-hand benzothiophene group, have been prepared. The compound with a thiazole unit with no substituent on the reaction-center carbon atom reveals an unprecedented transformation upon light irradiation. When the 4-position of thiazole is protected by a methyl group, the compounds show high photosensitivity and photochromic properties. In this case, light irradiation affords new compounds with [5]helicene structures featuring the highest redshifted absorption maxima reported to date.
International Collaborative Laboratory, Center for Frontier Science and Technology NAIST-CEMES, 29, rue Jeanne Marvig, BP 94347, 31055 Toulouse (France). o-galangau@ms.naist.jp.|Graduate School of Materials Science, Nara Institute of Science and Technology, NAIST, 8916-5 Takayama, Ikoma, Nara 630-0192 (Japan), Fax: (+81) 743-72-6179. o-galangau@ms.naist.jp.
Olivier
O
Galangau
International Collaborative Laboratory, Center for Frontier Science and Technology NAIST-CEMES, 29, rue Jeanne Marvig, BP 94347, 31055 Toulouse (France).
Takuyama
T
Nakashima
Laboratoire Interfaces, Traitements, Organisation et Dynamique des Systèmes (ITODYS), CNRS UMR 7086, Université Paris 7 - Paris Diderot, Sorbonne Paris Cité, Bâtiment Lavoisier, 15 rue Jean Antoine de Bïf, 75205 Paris Cedex 13 (France).
François
F
Maurel
International Collaborative Laboratory, Center for Frontier Science and Technology NAIST-CEMES, 29, rue Jeanne Marvig, BP 94347, 31055 Toulouse (France). tkawai@ms.naist.jp.|Graduate School of Materials Science, Nara Institute of Science and Technology, NAIST, 8916-5 Takayama, Ikoma, Nara 630-0192 (Japan), Fax: (+81) 743-72-6179. tkawai@ms.naist.jp.
Tsuyoshi
T
Kawai
arylation; helical structures; isomerization; photochromism; substituent effects