2-oxobutanoic acid
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| General | ||||||||||||||||||||||
| Surname | 2-oxobutanoic acid | |||||||||||||||||||||
| other names |
2-oxobutyric acid |
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| Molecular formula | C 4 H 6 O 3 | |||||||||||||||||||||
| Brief description |
colorless crystals |
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| properties | ||||||||||||||||||||||
| Molar mass | 102.09 g · mol -1 | |||||||||||||||||||||
| Physical state |
firmly |
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| density |
1.2 g cm −3 (20 ° C) |
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| Melting point |
31-34 ° C |
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| boiling point |
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| solubility |
moderate in water (100 g l −1 at 20 ° C) |
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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-oxobutanoic acid is an aliphatic ketocarboxylic acid that is derived from butyric acid. Their flash point is 81 ° C. It is found in the metabolism of numerous amino acids and is a breakdown product of both cystathionine and threonine .
presentation
2-Oxobutanoic acid can be prepared from propionyl chloride , which is first converted into propionic acid nitrile with silver cyanide . The desired compound is then formed from this by hydrolysis with hydrochloric acid .
Another possible synthesis is based on diethyl oxalate , which is converted to ethyl methyl oxalate in a Claisen condensation with ethyl propionate and sodium ethanolate . When boiling with sulfuric acid , the ester is first cleaved and then decarboxylated , which leads to the desired end product.
Reactions
The reduction of 2-oxobutanoic acid with sodium amalgam produces 2-hydroxybutanoic acid .
Derived connections
The sodium salt of 2-oxobutanoic acid is registered under the CAS number 2013-26-5 and melts at 210 ° C. It is used as a substrate in the determination of lactate dehydrogenase - isoenzymes used.
The ethyl ester can be made from the acid and ethanol with benzene and p-toluenesulfonic acid . The synthesis of the methyl ester was carried out with methanol with the addition of chlorotrimethylsilane .
Individual evidence
- ↑ a b c d data sheet 2-oxobutanoic acid (PDF) from Merck , accessed on May 20, 2010.
- ↑ David R. Lide: CRC Handbook of Chemistry and Physics A Ready-reference Book of Chemical and Physical Data . CRC Press, 1995, ISBN 978-0-8493-0595-5 ( limited preview in Google Book Search).
- ↑ a b c d data sheet 2-Oxobutyric acid, ≥95%, FG from Sigma-Aldrich , accessed on December 1, 2019 ( PDF ).
- ↑ Entry on 2-Ketobutyric acid in the Human Metabolome Database (HMDB) , accessed on September 24, 2013.
- ^ L. Claisen , E. Moritz: "Ueber Propionylformensäure" in reports of the German chemical society , 1880 , 13 , pp. 2121-2122 ( full text )
- ^ E. Arnold: "Ueber Methyl- und Aethyloxalessigester" in Justus Liebig's Annalen der Chemie 1888 , 246 (3), pp. 329-338. doi : 10.1002 / jlac.18882460305
- ^ F. Beilstein: "Handbuch derorganischen Chemie", 3rd edition, 1st volume. Verlag Leopold Voss, 1893. pp. 590-591. Full text
- ↑ a b Data sheet Sodium 2-oxobutyrate, powder from Sigma-Aldrich , accessed on December 1, 2019 ( PDF ).
- ↑ D. Ferri, T. Bürgi, A. Baiker : "Conformational isomerism of a-ketoesters. A FTIR and ab initio study" in J. Chem. Soc., Perkin Trans. 2 2000 , p. 221-228
- ↑ Dissertation "Total synthesis of camptothecin", Deshan Liu, Georg-August-Universität Göttingen, 2008, p. 100.