Angelic acid
Structural formula | ||||||||||||||||
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General | ||||||||||||||||
Surname | Angelic acid | |||||||||||||||
other names |
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Molecular formula | C 5 H 8 O 2 | |||||||||||||||
Brief description |
pale yellow solid |
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properties | ||||||||||||||||
Molar mass | 100.05 g mol −1 | |||||||||||||||
Physical state |
firmly |
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density |
1.01 g cm −3 |
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Melting point |
45-46 ° C |
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boiling point | ||||||||||||||||
Refractive index |
1.4434 (47 ° C) |
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safety instructions | ||||||||||||||||
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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 |
Angelica acid , systematically ( Z ) -2-methyl-2-butenoic acid, is an unsaturated and short-chain, methyl-branched fatty acid , a monocarboxylic acid in the group of alkenoic acids . It occurs in the real angelica ( Angelica archangelica ), from whose roots it was first isolated in 1842 by Ludwig Andreas Buchner . Angelica acid is also found in other umbelliferae and other plant species. Angelic acid was also found in the defensive secretions of certain ground beetles .
The substance is volatile, has a sour taste and a pungent odor. At room temperature it is present as a crystalline solid. The crystal structure is monoclinic prismatic.
The isomeric ( E ) -2-methyl-2-butenoic acid is also called tiglic acid . Like tiglic acid, it is one of the hemiterpenes d. H. Terpenes that are made up of just one isoprene unit . The salts and esters of angelic acid are known as angelates.
Angelica acid was previously used as a sedative.
literature
- Andre S. Dreiding , Richard J. Pratt: The Carboxylation of cis- and trans-2-butenyl-2-lithium. A Stereospecific Synthesis of Angelic Acid. In: Journal of the American Chemical Society . 76, 1954, pp. 1902-1906, doi : 10.1021 / ja01636a049 .
Individual evidence
- ↑ a b c d data sheet (Z) -tiglic acid at thegoodscentscompany.com, accessed on July 20, 2016.
- ↑ 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. 3-344.
- ↑ harmonized classification for this substance . A labeling of 2-methylisocrotonic acid in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA), retrieved on November 6, 2019, is reproduced from a self-classification by the distributor . There is not yet a
- ↑ Dr. Buchner junior: About a peculiar volatile acid from the angelica root: a letter. In: Annals of Chemistry and Pharmacy . 42, 1842, pp. 226-233, doi : 10.1002 / jlac.18420420211 .
- ↑ E. Breitmeier: Terpenes. Teubner, 1999, ISBN 978-3-519-03548-0 , p. 20.