Diphenyl oxalate
From Wikipedia, the free encyclopedia
| Diphenyl oxalate | |
|---|---|
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| IUPAC name | Diphenyl oxalate |
| Other names | Diphenylethandioate, oxalic acid diphenyl ester, Cyalume, DPO |
| Identifiers | |
| CAS number | [3155-16-6] |
| PubChem | |
| SMILES | O=C(Oc1ccccc1)C(=O)Oc2ccccc2 |
| Properties | |
| Molecular formula | C14H10O4 |
| Molar mass | 242.227 g/mol |
| Appearance | Solid |
| Melting point |
136°C |
| Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox disclaimer and references |
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Diphenyl oxalate (trademark name Cyalume) is a solid ester whose oxidation products are responsible for the chemiluminescence in a glowstick. It can be synthesized by fully esterifying phenol with oxalic acid. The reaction with hydrogen peroxide that diphenyl oxalate undergoes to produce a photon of light is shown below:
The reaction rate is pH dependent, and slightly alkaline conditions achieved by adding a weak base, e.g. sodium salicylate, will produce brighter light. The 2,4,6-trichlorophenole ester of oxalic acid is a solid and thus easier to handle. Furthermore, since trichlorophenolate is the better leaving group, the reaction will proceed faster, again producing brighter light, as compared to the phenole ester.
The following colors can be produced by using different dyes:
| Color | Compound |
|---|---|
| Blue | 9,10-Diphenylanthracene |
| Green | 9,10-Bis(phenylethynyl)anthracene |
| Yellow-green | Tetracene |
| Yellow | 1-Chloro-9,10-bis(phenylethynyl)anthracene |
| Orange | 5,12-Bis(phenylethynyl)-naphthacene, Rubrene, Rhodamine 6G |
| Red | Rhodamine B |
