Department of Chemistry
Synthesis and photophysical studies of oxazole rings containing compounds as electron accepting units
A series of oxazole derivatives, 5-methyl-2-(p-methylphenyl)-4-acetyl oxazole (MMPAO), 5-methyl-2-(p-methoxyphenyl)-4-acetyl oxazole (MOPAO), 5-methyl-2-(p-N,N′-dimethylamino-phenyl)-4-acetyl oxazole (MDMAPAO) and 5-methyl-2-(p-N,N′-diphenylaminophenyl)-4-acetyl oxazole (MDPAPAO) have been synthesized and studied to compare their photophysical properties. The UV-visible absorption spectra of MDMAPAO and MDPAPAO are bathochromatically shifted as compared to that of MMPAO and MOPAO. The fluorescence emission of MDPAPAO is very sensitive to the polarity of solvents. The magnitude of change in the dipole moment was calculated using the Lippert-Mataga equation. MDPAPAO shows the highest change in the dipole moment (Δu = 13.3D) than that of the other three oxazole derivatives. The spectral properties including fluorescence quantum yield and lifetime were determined in solvents with different polarities. MDPAPAO displays the highest fluorescence quantum yield and lifetime, following a bi-exponential fluorescent decay fashion. Our result demonstrates that the excited state of MDPAPAO possesses the property of intramolecular charge transfer. © 2012 Elsevier B.V. All rights reserved.
Charge transfer, Fluorescence, Interaction, Oxazole ring
Source Publication Title
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy
Zhang, Caihong, Lifeng Li, Hongjuan Wu, Zhixun Liu, Junfen Li, Guomei Zhang, Guangming Wen, Shaomin Shuang, Chuan Dong, and Martin M.F. Choi. "Synthesis and photophysical studies of oxazole rings containing compounds as electron accepting units." Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 102 (2013): 256-262.