Jonone

Violon is a redirect to this article. For other uses, see Violone and list of Orgelregister # V .

The ionone (also ionone , stress on the second syllable: Jon o ne ) form a group of substances that includes the individual substances α-, β- and γ-ionone and are derived from terpenes . The substances have a violet-like odor and are widespread natural substances found in many plants.

Occurrence

All three types of ionon have been found in the oils of various plants, especially berries , tea and tobacco . Violet oil contains approx. 22% α-ionone, β-ionone is found, for example, in henna , and tamarind contains γ-ionone. β-ionone is a breakdown product of β-carotene .

Both optical isomers [( R ) -α-ion and ( S ) -α-ion] of the α-ionone are found in nature.

The following table provides an overview of the individual substances and their properties.

Jonone
Surname	α-ionone	β-ionone	γ-ionone
Structural formula	( R ) -α-ionone ( S ) -α-ionone	β-ionone	( R ) -γ-ionone ( S ) -γ-ionone
other names	Violon ( E ) -Megastigma-4,7-dien-9-one ( E ) -4- (2,6,6-trimethyl-2-cyclohexen-1-yl) -3-buten-2-one	Boronion ( E ) -Megastigma-5 (13), 7-dien-9-one ( E ) -4- (2,6,6-trimethyl-1-cyclohexen-1-yl) -3-buten-2-one	( E ) -Megastigma-4,7-dien-9-one ( E ) -4- (2-methylen-6,6-dimethyl-cyclohexan-1-yl) -3-buten-2-one
CAS number	127-41-3 ( rac ) 24190-29-2 ( R ) 14398-36-8 ( S )	79-77-6	24190-32-7
	8013-90-9 (mixture)
PubChem	5282108	638014	5363741
Molecular formula	C 13 H 20 O
Molar mass	192.30 g mol −1
Physical state	liquid
Brief description	colorless to yellowish, viscous liquid ( R ) -enantiomer: with a violet-like, raspberry-like, floral odor ( S ) -enantiomer: with a woody-violet-like odor	colorless liquid with a woody-violet odor	-
density	0.93 g cm −3	0.95 g cm −3	-
Melting point	-	−49 ° C	-
boiling point	237 ° C	126–128 ° C (16 hPa)	-
Vapor pressure	0.13 Pa (20 ° C)	-	-
solubility	very bad in water		-
Optical activity	[α] D 23 : + 347 ° ( D ) [α] D 25 : 0 ° ( DL ) [α] D 27 : −406 ° ( L )	[α] D 27 : 0 °	-
Refractive index	1.5016 (20 ° C) ( D ) 1.5041 (20 ° C) ( DL ) 1.5000 (25 ° C) ( L )	1.5198 (20 ° C)	-
GHS labeling	danger	Caution	no classification available
H and P phrases	334	315	see above
	no EUH phrases	no EUH phrases	see above
	261-342 + 311	no P-phrases	see above

Extraction and presentation

The ionones can either be obtained from appropriate vegetable oils or produced synthetically .

Violet oils - e.g. B. from the Parma and Victoria violets ( Viola odorata ) - contain ionons.

In 1893 Wilhelm Haarmann developed and patented a process for the synthesis of α- and β-ionone from citral for Haarmann & Reimer . Then citral is condensed with acetone in a basic medium . This creates a pseudo-jonon .

When heated with dilute acid, this can be cyclized to a mixture of α- and β-ionone .

The ratio of α- to β-ionone changes depending on the reaction conditions. Cyclization with phosphoric acid mainly produces α-ionone, with sulfuric acid β-ionone.

By reacting pseudo-ionone with boron trifluoride and concentrated acetic acid , pure β-ionone can be produced with high yield.

The double bond in the side chain , which is normally in the trans configuration, can be converted into the cis configuration by ultraviolet radiation .

use

Jonon is used in large quantities in the fragrance industry, mostly in flower or fantasy compositions. Depending on the area of ​​application, mixtures of isomers or individual isomers, all of which differ in their fragrance, are used here. Jonones are also used to a lesser extent for the production of flavors.

They are also used to produce the damascenones and isomethylionones ( α-isomethylionone ) that are important in perfumery .

β-ionone is also an important starting substance for the production of retinol and carotenes .

Biological importance

Ions can still be smelled in very low concentrations by humans . For β-ionone the odor threshold is 10 ⁻⁷ mg per liter of air or 0.1 ppb , for ( R ) -γ-ionone at 11 ppb and for ( S ) -γ-ionone 0.07 ppb.

safety instructions

The LD ₅₀ value (rat, oral) is 4590 mg kg ⁻¹ for α-ionone and 2920 mg kg ⁻¹ for β-ionone .

Jonons have an allergenic potential and should therefore be handled with gloves if possible.

α-ionone is also assigned to water hazard class 2 (hazardous to water).

Individual evidence

1. ↑ Bernd Schäfer: Natural substances in the chemical industry. Spektrum Akademischer Verlag, 2007, ISBN 978-3-8274-1614-8 , p. 73.
2. ↑ ^{a b} entry on Jonone. In: Römpp Online . Georg Thieme Verlag, accessed on May 25, 2014.
3. ↑ ^{a b c} data sheet α-Jonon (PDF) from Merck , accessed on February 20, 2010.
4. ↑ ^{a b} data sheet β-ionon (PDF) from Carl Roth , accessed on February 20, 2010.
5. ↑ ^{a b} data sheet β-ionon from Sigma-Aldrich , accessed on February 20, 2010 ( PDF ).
6. ↑ Jonone data sheet at Acros, accessed on February 20, 2010.
7. ↑ ^{a b c d e f g h} CRC Handbook of Chemistry and Physics , 60th Edition, CRC Press, 1980.
8. ↑ Data sheet a-Ionone from Sigma-Aldrich , accessed on May 3, 2011 ( PDF ).
9. ↑ Bernd Schäfer: Natural substances in the chemical industry. Spektrum Akademischer Verlag, 2007, ISBN 978-3-8274-1614-8 , pp. 64–65.
10. ↑ Elisabetta Brenna, Claudio Fuganti, Stefano Serra, Philip Kraft: Optically Active Ionones and Derivatives: Preparation and Olfactory Properties. In: Eur. J. Org. Chem. 2002, pp. 967-978.

literature

• D. Martinetz, R. Hartwig: Pocket book of fragrances. 1st edition. Verlag Harri Deutsch, Frankfurt am Main 1998, ISBN 3-8171-1539-3 .
• E. Breitmaier: Terpenes. (= Teubner study books). 1st edition. Stuttgart et al. 1999, ISBN 3-519-03548-0 .
• Entry to Jonone. In: Römpp Online . Georg Thieme Verlag, accessed on May 25, 2014.
• H. Beyer, W. Walter, W. Francke: Textbook of organic chemistry. 23rd edition. S. Hirzel Verlag, Stuttgart / Leipzig 1998, ISBN 3-7776-0808-4 .