Cyanoacetic acid
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| General | |||||||||||||||||||
| Surname | Cyanoacetic acid | ||||||||||||||||||
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| Molecular formula | C 3 H 3 NO 2 | ||||||||||||||||||
| Brief description |
colorless, hygroscopic crystals |
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| properties | |||||||||||||||||||
| Molar mass | 85.06 g mol −1 | ||||||||||||||||||
| Physical state |
firmly |
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| density |
1.26 g cm −3 |
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| Melting point |
66-70 ° C |
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| solubility |
very light in water (1000 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 . | |||||||||||||||||||
Cyanoacetic acid ( cyanoacetic acid ) is a colorless, crystalline, unpleasant smelling, hygroscopic solid. It is a CH-acidic compound, so it is suitable for the Knoevenagel condensation with ketones and aldehydes . At higher temperatures it decomposes with decarboxylation to form carbon dioxide and acetonitrile .
Extraction and presentation
It is produced from chloroacetic acid with alkali metal cyanides by Kolbe nitrile synthesis .
use
Hydrolysis to malonic acid , production of cyanoacetic acid esters (increased carbonyl activity of the ester group due to the cyanide group), as a reagent for the Michael addition and for the preparation of β-ketonitriles and β-cyano enamines . Plays a special role the implementation of cyanoacetic with methanal ( formaldehyde ) for producing Cyanoacrylsäureestern , the in superglues ( superglues monomers used). Diethyl malonate cannot be obtained by direct esterification of malonic acid because decarboxylation occurs when heated , but is made from the sodium salt of cyanoacetic acid with ethanol and concentrated mineral acids with ethanol .
Individual evidence
- ↑ a b Entry on cyano (o) acetic acid. In: Römpp Online . Georg Thieme Verlag, accessed on June 8, 2014.
- ↑ a b c d e f Entry on cyanoacetic acid in the GESTIS substance database of the IFA , accessed on January 8, 2020(JavaScript required) .
- ↑ a b Data sheet cyanoacetic acid (PDF) from Merck , accessed on March 23, 2011.