Turning on fluorescent emission from C-alkylation on quinoxaline derivatives.
Reduction on imine moiety (C=N) of quinoxalines by alkyl-/aryllithiums led to a geometrical change on the quinoxaline ring, thereby perturbing the electronic structure to turn on fluorescence emission. Such a structural change resulted in interrupted cyclic-ring systems with electron-donating amine (sp(3)-type) and electron-accepting imine (sp(2)-type) units bridged by a phenylene unit. Through either alkylation or arylation, a highly polarized electron donor-electron acceptor bipolar system was established in a single molecule with dramatically enhanced PL efficiency (up to 60%).
Son
Ho-Jin
HJ
Department of Materials Chemistry, Sejong Campus, Korea University, Chochiwon, Chung-Nam 339-700, South Korea.
Han
Won-Sik
WS
Wee
Kyung-Ryang
KR
Yoo
Dae-Hwan
DH
Lee
Jong-Ho
JH
Kwon
Soon-Nam
SN
Ko
Jaejung
J
Kang
Sang Ook
SO