2,7-dichlorofluorescein
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| General | ||||||||||||||||
| Surname | 2,7-dichlorofluorescein | |||||||||||||||
| other names |
2 ', 7'-dichloro-3', 6'-dihydroxyspiro [2-benzofuran-3,9'-xanthene] -1-one ( IUPAC ) |
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| Molecular formula | C 20 H 10 Cl 2 O 5 | |||||||||||||||
| Brief description |
orange-yellow odorless solid |
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| properties | ||||||||||||||||
| Molar mass | 401.20 g mol −1 | |||||||||||||||
| Physical state |
firmly |
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| Melting point |
> 300 ° C (decomposition) |
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| solubility |
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| As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions . | ||||||||||||||||
2,7-dichlorofluorescein is a fluorescent dye from the group of triphenylmethane dyes . It is a derivative of fluorescein that differs from it by having two additional chlorine atoms .
use
2,7-dichlorofluorescein is used as an indicator in the titration according to Fajans (argentometry).
A 0.2% solution of 2,7-dichlorofluorescein in methanol can be used for the detection of sweeteners in thin-layer chromatography .
Individual evidence
- ↑ a b c d e f g data sheet 2 ', 7'-dichlorofluorescein from AlfaAesar, accessed on December 21, 2019 ( PDF )(JavaScript required) .
- ↑ IM Kolthoff, WM Lauer, CJ Sunde: the use of Dichlorofluorescein as an Adsorption Indicator for the Argentometric Titration of Chlorides . In: Journal of the American Chemical Society . tape 51 , no. 11 , 1929, pp. 3273-3277 , doi : 10.1021 / ja01386a014 .
- ↑ Reinhard Mattisek, Gabriele Steiner, Markus Fischer: Food Analysis . 4th edition. Springer, Berlin 2010, ISBN 978-3-540-92205-6 .