Syntheses and photophysical properties of BF2 complexes of curcumin analogues.
Stable tetracoordinated organoboron complexes as classic fluorescent molecules have found various applications in material and medical sciences. A new class of curcumin-BF2 complexes has been prepared from the condensation of 2,2-difluoro-1,3-dioxaborylpentadione with a variety of aldehydes and its photophysical properties were characterized. Systematic variations were observed in the absorption spectra of these curcumin-BF2 dyes in solutions, which are well correlated with their structural features, including characteristics of the aromatic groups and presence of a para electron-donating substituent. Strong fluorescence that is tunable from 500 to 800 nm via variation of the polarity of the solvent and a moderate to good fluorescence quantum yield ranging from 0.24 to 0.58 in dichloromethane were observed in curcumin-BF2 complexes 1. By contrast, their asymmetrical analogue, curcumin-BF2 complexes 3 exhibit much lower fluorescence quantum yields. Besides their excellent photostabilities, these curcumin-BF2 dyes also show singlet oxygen generating capabilities.
Laboratory of Functional Molecular Solids, Ministry of Education, Anhui Laboratory of Molecule-Based Materials, School of Chemistry and Materials Science, Anhui Normal University, Wuhu, Anhui 241000, China. haoehong@mail.ahnu.edu.cn jiao421@mail.ahnu.edu.cn.
Guifeng
G
Bai
Changjiang
C
Yu
Chi
C
Cheng
Erhong
E
Hao
Yun
Y
Wei
Xiaolong
X
Mu
Lijuan
L
Jiao
D001896:Boron Compounds / Q000737:chemistry*; D045744:Cell Line, Tumor; D018360:Crystallography, X-Ray; D003474:Curcumin / Q000031:analogs & derivatives / Q000737:chemistry*; D005456:Fluorescent Dyes / Q000138:chemical synthesis* / Q000737:chemistry*; D006801:Humans; D008856:Microscopy, Fluorescence; D008958:Models, Molecular; D015394:Molecular Structure; D055668:Photochemical Processes
D001896:Boron Compounds; D005456:Fluorescent Dyes; C579460:boron difluoride; D003474:Curcumin