| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 5217439 | Tetrahedron | 2013 | 6 Pages |
Abstract
A series of C-8â²-oxime-appended spirobenzopyrans 4a-4d were synthesized and developed as fluorescent pH ratiometric probes operative in HEPES/ACN (8:2, v/v) buffer solutions. Acidochromic conversion of spirobenzopyran to merocyanine open form can facilitate the subsequent enol-keto tautomerization giving dual emissive peaks via the excited state intramolecular proton transfer (ESIPT) mechanism. The pH titrations of 4a show a 68-fold increase in ratiometric intensities ratio (I645Â nm/I522Â nm) when the pH was switched from 8.0 to 4.0 with a pKa value of 5.90.
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Related Topics
Physical Sciences and Engineering
Chemistry
Organic Chemistry
Authors
Yim-Pan Chan, Li Fan, Qihua You, Wing-Hong Chan, Albert W.M. Lee, Shaomin Shuang,