Benzothiazole
| Benzothiazole | |
|---|---|
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 |
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| IUPAC name 1,3-Benzothiazole | |
| Identifiers | |
| CAS number | 95-16-9  |
| PubChem | 7222 |
| ChemSpider | 6952 |
| UNII | G5BW2593EP |
| ChEBI | CHEBI:45993 |
| ChEMBL | CHEMBL510309 |
| Jmol-3D images | Image 1 |
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| Properties | |
| Molecular formula | C7H5NS |
| Molar mass | 135.19 g mol−1 |
| Density | 1.238 g/mL |
| Melting point | 2 °C; 36 °F; 275 K |
| Boiling point | 227 to 228 °C; 441 to 442 °F; 500 to 501 K |
| Supplementary data page | |
| Structure and properties |
n, εr, etc. |
| Thermodynamic data |
Phase behaviour Solid, liquid, gas |
| Spectral data | UV, IR, NMR, MS |
(verify) (what is: / ?)Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa) | |
| Infobox references | |
Benzothiazole is an aromatic heterocyclic compound with the chemical formula C
7H
5NS. It is colorless, slightly viscous liquid. Although the parent compound, benzothiazole is not widely used, many of its derivatives are found in commercial products or in nature. A derivative of benzothiazole is the light-emitting component of luciferin, found in fireflies.
Structure and preparation
Benzothiazoles consist of a 5-membered 1,3-thiazole ring fused to a benzene ring. The nine atoms of the bicycle and the attached substituents are coplanar.
Benzothiazole are prepared by treatment of 2-aminobenzenethiol with acid chlorides:[1]
- C6H4(NH2)SH + RC(O)Cl → C6H4(NH)SCR + HCl + H2O
Uses
This heterocyclic scaffold is readily substituted at the unique methyne centre in the thiazole ring. Its a thermally stable electron-withdrawing moiety with numerous applications in dyes such as thioflavin. Some drugs contain this group, an example being riluzole. The heterocycle is found in nature.[2] Accelerators for the vulcanization of rubber are based on 2-mercaptobenzothiazole.[3] This ring is a potential component in nonlinear optics (NLO).[4]
See also
- Benzothiazoles are related to thiazoles, which lack the fused benzene ring.
- Benzoxazoles, which substitute an oxygen for the sulfur atom.
References
- ↑ T. E. Gilchrist "Heterocyclic Chemistry" 3rd Edition, Longman, 1992.
- ↑ Lucille Le Bozec, Christopher J. Moody "Naturally Occurring Nitrogen–Sulfur Compounds. The Benzothiazole Alkaloids" Australian Journal of Chemistry 62(7) 639–647.doi:10.1071/CH09126
- ↑ Hans-Wilhelm Engels, Herrmann-Josef Weidenhaupt, Manfred Pieroth, Werner Hofmann, Karl-Hans Menting, Thomas Mergenhagen, Ralf Schmoll, Stefan Uhrlandt “Rubber, 4. Chemicals and Additives” in Ullmann's Encyclopedia of Industrial Chemistry 2004, Wiley-VCH, Weinheim. doi:10.1002/14356007.a23_365.pub2
- ↑ Hrobarik, P.; Sigmundova, I.; Zahradnik, P.; Kasak, P.; Arion, V.; Franz, E.; Clays, K. (2010). "Molecular Engineering of Benzothiazolium Salts with Large Quadratic Hyperpolarizabilities: Can Auxiliary Electron-Withdrawing Groups Enhance Nonlinear Optical Responses?". Journal of Physical Chemistry C 114 (50): 22289–22302. doi:10.1021/jp108623d.