2-Chlorobenzoic acid
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| Names | |
|---|---|
| Preferred IUPAC name
2-Chlorobenzoic acid | |
| Other names
o-Chlorobenzoic acid | |
| Identifiers | |
3D model (JSmol) |
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| ChEBI | |
| ChEMBL | |
| ChemSpider | |
| ECHA InfoCard | 100.003.897 |
| KEGG | |
PubChem CID |
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| UNII | |
CompTox Dashboard (EPA) |
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| Properties | |
| C7H5ClO2 | |
| Molar mass | 156.57 g·mol−1 |
| Appearance | white solid |
| Melting point | 142 °C (288 °F; 415 K) |
| Boiling point | 285 °C (545 °F; 558 K) |
| log P | 2.039 [1] |
| Acidity (pKa) | 2.89 [2][3] |
| −83.56·10−6 cm3/mol | |
| Hazards | |
| Safety data sheet (SDS) | Oxford MSDS |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references | |
2-Chlorobenzoic acid is an organic compound with the formula ClC6H4CO2H. It is one of three isomeric chlorobenzoic acids, the one that is the strongest acid. This white solid is used as a precursor to a variety of drugs, food additives, and dyes.[4]
Synthesis and reactions
It is prepared by the oxidation of 2-chlorotoluene. The laboratory scale reaction employs potassium permanganate.[5] Alternatively it arises by the hydrolysis of α,α,α-trichloro-2-toluene.
The chloride is readily replaced by ammonia to 2-aminobenzoic acid. Similarly, the chloride is displaced by diphenylphosphide, leading to 2-diphenylphosphinobenzoic acid.
At elevated temperature it decarboxylates.[4]
Applications
Known uses include in the synthesis of: Mefenamic acid,[6] Amsacrine, Eproxindine, Diclofenac, Thiethylperazine, Meclofenamic acid,[7] Araprofen, Lucanthone, Tibric acid, Enfenamic acid, Chlorprothixene (actually 2-iodobenzoic acid according to cited patent).[8] Flufenamic acid[9][10][11]
References
- ↑ 1.2-Chlorobenzoic acid; C7H5ClO2; ChemSpider. Chemspider.com (2015). at
- ↑ Clayton, G. D. and F. E. Clayton (eds.). Patty's Industrial Hygiene and Toxicology: Volume 2A, 2B, 2C: Toxicology. 3rd ed. New York: John Wiley Sons, 1981-1982., p. 1838
- ↑ 2.2-Chlorobenzoic acid; C7H5ClO2 - PubChem. Pubchem.ncbi.nlm.nih.gov at
- 1 2 Takao Maki, Kazuo Takeda "Benzoic Acid and Derivatives" in Ullmann's Encyclopedia of Industrial Chemistry 2002, Wiley-VCH, Weinheim. doi:10.1002/14356007.a03_555.
- ↑ H. T. Clarke and E. R. Taylor (1943). "o-Chlorobenzoic acid". Organic Syntheses; Collected Volumes, vol. 2, p. 135.
- ↑ Lednicer, D., Mitscher, L. A. (1977). The organic chemistry of drug synthesis. 1. Wiley. ISBN 9780471521419.
- ↑ Castañer, J., Arrigoni-Martelli, E. (1978). "Meclofenamic Acid". Drugs of the Future. 3 (4): 307. doi:10.1358/dof.1978.003.04.277278. ISSN 0377-8282. Retrieved 28 August 2026.
- ↑ Lednicer, D. (2009). Strategies for organic drug synthesis and design (2nd ed ed.). Wiley. ISBN 9780470190395.
{{cite book}}:|edition=has extra text (help) - ↑ Synthesis of Essential Drugs. Elsevier. 2006. doi:10.1016/B978-0-444-52166-8.X5000-6. ISBN 9780444521668.
- ↑ Moffett, R. B., Aspergren, B. D. (April 1960). "Aminoalkylphenothiazines". Journal of the American Chemical Society. 82 (7): 1600–1607. doi:10.1021/ja01492a022. Retrieved 28 August 2026.
- ↑ Carrasco, R., Pellón, R. F., Elguero, J., Goya, P., Páez, J. A. (July 1989). "The Use of Ultrasound in the Synthesis of N-Thranilic Acids by the Ullmann Goldberg Reaction". Synthetic Communications. 19 (11–12): 2077–2080. doi:10.1080/00397918908052600. Retrieved 28 August 2026.
