Valeraldehyde
Structural formula | ||||||||||||||||||||||
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General | ||||||||||||||||||||||
Surname | Valeraldehyde | |||||||||||||||||||||
other names | ||||||||||||||||||||||
Molecular formula | C 5 H 10 O | |||||||||||||||||||||
Brief description |
colorless liquid with a pungent odor |
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External identifiers / databases | ||||||||||||||||||||||
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properties | ||||||||||||||||||||||
Molar mass | 86.13 g mol −1 | |||||||||||||||||||||
Physical state |
liquid |
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density |
0.81 g cm −3 (20 ° C) |
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Melting point |
−92 ° C |
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boiling point |
103 ° C |
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Vapor pressure |
36 hPa (20 ° C) |
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solubility |
poorly soluble in water (14 g l −1 at 20 ° C) |
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Refractive index |
1.3944 (20 ° C) |
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safety instructions | ||||||||||||||||||||||
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MAK |
Switzerland: 50 ml m −3 or 175 mg m −3 |
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Toxicological data | ||||||||||||||||||||||
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions . Refractive index: Na-D line , 20 ° C |
Valeraldehyde (according to IUPAC nomenclature: n- pentanal , more rarely also called amylaldehyde ) is an organic-chemical compound from the group of aldehydes . With its isomeric compounds isovaleraldehyde , 2-methylbutyraldehyde and pivalaldehyde , it forms the group of pentanals .
Extraction and presentation
Valeraldehyde is industrially by hydroformylation of 1-butene at temperatures of 70 - 200 bar made - 150 ° C and pressures of from 10th The catalyst systems used are usually rhodium bisphosphite complexes with sterically hindered organic secondary amines which have a selectivity for n- pentanal of at least 90%. The complete reaction takes place in bubble column reactors or stirred tank reactors . C4 mixtures such as the so-called raffinate II obtained in steam cracking can also be used as starting material .
properties
Valeraldehyde forms highly flammable vapor-air mixtures. The compound has a flash point of 6 ° C. The lower explosion limit (LEL) is 1.1 vol.% (50 g · m −3 ). The ignition temperature is 205 ° C. The substance therefore falls into temperature class T3.
use
Valeraldehyde is used in various flavors (e.g. fruit flavors) and as a vulcanization accelerator. 2-Propyl-2-heptenal is obtained from valeraldehyde by aldol condensation , which is hydrogenated to the saturated branched alcohol 2-propylheptanol (2-PH) . This serves as a starting material for the PVC plasticizer di-2-propylheptyl phthalate and, after ethoxylation with 5 or 7 EO units, for nonionic APEO (alkylphenol ethoxylate) -free detergents.
safety instructions
The fumes are irritating to the eyes, respiratory tract and skin. Long exposure can lead to pulmonary edema . Polymerization occurs with amines, ammonia and alkaline substances.
Individual evidence
- ↑ Entry on VALERALDEHYDE in the CosIng database of the EU Commission, accessed on May 6, 2020.
- ↑ a b c d e f g h i j k l Entry on valeraldehyde in the GESTIS substance database of the IFA , accessed on August 21, 2017(JavaScript required) .
- ↑ David R. Lide (Ed.): CRC Handbook of Chemistry and Physics . 90th edition. (Internet version: 2010), CRC Press / Taylor and Francis, Boca Raton, FL, Physical Constants of Organic Compounds, pp. 3-414.
- ↑ Swiss Accident Insurance Fund (Suva): Limit values - current MAK and BAT values (search for 110-62-3 or valerianaldehyde ), accessed on September 30, 2019.
- ↑ WO 2009/146985 Evonik OXENO GmbH .
- ↑ Dirk Fridag, Robert Franke, Dieter Hess, Markus Schwarz, Katrin Marie Dyballa, Hans-Gerd Lueken, Bart Hamers, Uwe Ernst: Long-term stable process for the production of C5 aldehydes. In: Google Patents. Evonik Degussa GmbH, October 12, 2012, accessed on December 22, 2018 (German, English, French).
- ^ A b E. Brandes, W. Möller: Safety-related parameters - Volume 1: Flammable liquids and gases , Wirtschaftsverlag NW - Verlag für neue Wissenschaft GmbH, Bremerhaven 2003.