کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5272091 | 1385457 | 2009 | 6 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: 3-Hydroxybenzo[g]quinolones: dyes with red-shifted absorption and highly resolved dual emission 3-Hydroxybenzo[g]quinolones: dyes with red-shifted absorption and highly resolved dual emission](/preview/png/5272091.png)
New derivatives of 3-hydroxyquinolone (3HQ) with a fused benzene ring (3-hydroxybenzo[g]quinolones) have been synthesized. They display a remarkable red shift of their absorption spectrum in comparison with other 3HQ analogs allowing their excitation by common He/Cd and Ar-ion lasers. As a result of their irreversible excited-state intramolecular proton transfer (ESIPT) reaction, they display a dual fluorescence in a series of solvents of varying polarities, starting from toluene to methanol. The dual emission of these dyes correlates well with solvent H-bond basicity, which is connected with the effect of this solvent property on the kinetics of the ESIPT reaction. In addition to their red-shifted absorption and fluorescence, these new derivatives show a larger separation of their two emission bands and a more appropriate range of their intensity ratio than the previously synthesized 3HQs. These properties allow an improved ratiometric evaluation of the local H-bond basicity of unknown environments, which will favor future applications of the new dyes in polymer and biological sciences.
Journal: Tetrahedron Letters - Volume 50, Issue 33, 19 August 2009, Pages 4714-4719