Dramatic substituent effects on the photoluminescence of boron complexes of 2-(benzothiazol-2-yl)phenols.
Substituents can induce dramatic changes in the photoluminescence properties of N,O-chelated boron complexes. Specifically, the boron complexes of 2-(benzothiazol-2-yl)phenols become bright deep blue- and orange-red-emitting materials depending on amino substituents at the 5- and 4-positions of 2-(benzothiazol-2-yl)phenol, respectively. Absorption and emission data show that the resulting boron complexes have little or small overlap between the absorption and emission spectra and, furthermore, X-ray crystal structures for both the blue and orange-red complexes indicate the absence of π-π stacking interaction in the crystal-packing structures. These features endow the boron complexes with bright and strong photoluminescence in the solid state, which distinguishes itself from the typical boron complexes of dipyrromethenes (BODIPYs). A preliminary study indicates that the blue complexes have promising electro-optical characteristics as dopant in an organic light-emitting diode (OLED) device and show chromaticity close to an ideal deep blue. The substituent effects on the photoluminescent properties may be used to tune the desired emission wavelength of related boron or other metal complexes.
Department of Chemistry, Pohang University of Science and Technology (POSTECH), San 31, Hyoja-dong, Pohang, 790-784, Republic of Korea.
Mithun
M
Santra
Hyunsoo
H
Moon
Min-Ho
MH
Park
Tae-Woo
TW
Lee
Young Kook
YK
Kim
Kyo Han
KH
Ahn
D000042:Absorption; D052160:Benzothiazoles / Q000138:chemical synthesis* / Q000737:chemistry*; D001896:Boron Compounds / Q000138:chemical synthesis* / Q000737:chemistry*; D004396:Coloring Agents / Q000737:chemistry*; D018360:Crystallography, X-Ray; D049449:Luminescence; D015394:Molecular Structure; D010084:Oxidation-Reduction; D010636:Phenols / Q000138:chemical synthesis* / Q000737:chemistry*; D010777:Photochemistry
D052160:Benzothiazoles; D001896:Boron Compounds; D004396:Coloring Agents; D010636:Phenols