Synthesis and properties of triply-bridged syn-carbazolophanes.
The intramolecular [2 + 2] photocycloaddition of alpha,omega-bis(3,6-divinyl-N-carbazolyl)alkanes 3 afforded triply bridged syn-[2.2.n](3,6,9)carbazolophanes 4a-6a (n = 4) and 4b,5b (n = 5) composed of isomers derived from the difference in the direction of cyclobutane rings. In major isomers 4a and 4b, excimer fluorescence was observed, the maximum position remarkably depending on the tether length.
Nakamura
Yosuke
Y
Department of Chemistry, Gunma University, Tenjin-cho, Kiryu, Gunma 376-8515, Japan. nisimura@chem.gunma-u.ac.jp
Kaneko
Masayoshi
M
Tani
Keita
K
Shinmyozu
Teruo
T
Nishimura
Jun
J