Highly emissive organic solids containing 2,5-diboryl-1,4-phenylene unit.
We disclosed a series of pi-conjugated systems containing 2,5-bis(dimesitylboryl)-1,4-phenylene as the core unit and electron-donating amino groups at the terminal positions. The extension of the ppi-pi* conjugation in the diborylphenylene moiety along the short axis of the pi-conjugated framework as well as the incorporation of two bulky dimesitylboryl groups at the para-positions makes this moiety act as a unique bulky pi-electron-accepting unit. As a consequence, these systems behave like donor-acceptor-donor quadrupolar pi-electron systems and show a large solvatochromism in the fluorescence spectra. Moreover, these organoboron pi systems exhibit intense fluorescence even in the solid state with the quantum yields of 0.73-0.90.
Zhao
Cui-Hua
CH
Department of Chemistry, Graduate School of Science, Nagoya University, and SORST, Japan Science and Technology Agency, Chikusa, Nagoya 464-8602, Japan.
Wakamiya
Atsushi
A
Inukai
Yuko
Y
Yamaguchi
Shigehiro
S