Cinnamaldehyde

Structural formula
Structural formula of trans -cinnamaldehyde
General
Surname	Cinnamaldehyde
other names	Cinnamaldehyde Cinnamal trans -3-phenyl-2-propenal ( E ) -3-phenylprop-2-en-1-al γ-phenylacrolein FEMA  2286
Molecular formula	C 9 H 8 O
Brief description	yellowish, oily liquid with an intense smell of cinnamon
External identifiers / databases
CAS number 14371-10-9 ( trans -cinnamaldehyde) 57194-69-1 ( cis -cinnamalaldehyde) 104-55-2 (unspec.) EC number 604-377-8 ECHA InfoCard 100.111.079 PubChem 637511 ChemSpider 553117 Wikidata Q204036
properties
Molar mass	132.16 g mol −1
Physical state	liquid
density	1.05 g cm −3 (20 ° C)
Melting point	−8 ° C
boiling point	246-253 ° C
Vapor pressure	3.85 Pa (25 ° C)
solubility	heavy in water (1 g l −1 at 20 ° C) miscible with ethanol , diethyl ether and chloroform
Refractive index	1.6219 (20 ° C)
safety instructions
GHS labeling of hazardous substances Caution H and P phrases H: 312-315-317-319 P: 280-302 + 352-305 + 351 + 338
Toxicological data	2220 mg kg −1 ( LD 50 ,  rat ,  oral )
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

Cinnamaldehyde ( 3-phenyl-2-propenal , FEMA  2286 ) is a yellowish , oily liquid that smells intensely of cinnamon . It is the main flavoring of the cinnamon bark and was first isolated from cinnamon oil in 1834 . Cinnamaldehyde is an organic chemical compound with the empirical formula C ₉ H ₈ O and belongs to the group of phenylpropanoids . It belongs to the aromatic group and is an α, β-unsaturated aldehyde .

Isomerism

The carbon-carbon double bond in the side chain of cinnamaldehyde is typically trans -configured. The isomeric cis -cinnamic aldehyde [synonym: ( Z ) -cinnamic aldehyde] is of little importance. The information in this article relates only to trans -cinnamaldehyde [synonym: ( E ) -cinnamaldehyde].

Isomers of cinnamaldehyde
Surname	trans -cinnamaldehyde	cis -cinnamaldehyde
other names	( E ) -cinnamaldehyde	( Z ) -cinnamaldehyde
Structural formula
CAS number	14371-10-9	57194-69-1
	104-55-2 (unspec.)
EC number	604-377-8	-
	203-213-9 (unspec.)
ECHA info card	100.111.079	-
	100.002.922 (unspec.)
PubChem	637511	6428995
	307 (unspec.)
Wikidata	Q204036	Q27161918
	Q60041699 (unspec.)

History and occurrence

Cinnamaldehyde was isolated from cinnamon oil by Jean-Baptiste Dumas and Eugène-Melchior Péligot in 1834 and synthesized by Luigi Chiozza in 1856 .

Cinnamaldehyde occurs naturally in cinnamon bark oil (42–68%) and cassia oil (up to 90%), but to a lesser extent also in the leaves of the cinnamon tree and in many other essential oils.

• 

  Bark of the cinnamon tree ( Cinnamomum verum )

• 

  Cinnamon oil is extracted from the bark of the cinnamon tree ( Cinnamomum verum ), 65–75% of which is cinnamaldehyde.

presentation

Natural sources

Cinnamaldehyde is obtained from the bark (and, to a lesser extent, the leaves) of the cinnamon tree by steam distillation .

Technical syntheses

Trans- cinnamaldehyde can be prepared in a 60% yield analogous to cinnamic acid by means of aldol condensation from benzaldehyde and acetaldehyde .

The preparation is also possible by Vilsmeier formylation of styrene in 30% yield.

The cis -cinnamaldehyde can be obtained from the trans -compound by a photochemical isomerization :

properties

COSMO surface of the cinnamaldehyde
(blue = negative, red = positive equalizing charge)

Physical Properties

Cinnamaldehyde is a yellowish, oily liquid that smells intensely of cinnamon and which gradually oxidizes to cinnamic acid in the air . It melts at −8  ° C and boils at 251 ° C at normal pressure . It dissolves very poorly in water (1.1 g / l at 20 ° C), but it is miscible with ethanol , diethyl ether and chloroform .

Chemical properties

Cinnamaldehyde is sensitive to light, heat, alkalis and some metals and shows the usual aldehyde and olefin reactions.

It can be reduced to cinnamon alcohol in 75% yield by Meerwein-Ponndorf-Verley reduction .

Cinnamic acid is formed through autoxidation in air .

Stronger oxidizing agents such as potassium permanganate or ozone oxidize cinnamaldehyde to benzoic acid.

Hydrocinnamaldehyde is formed by hydrogenation of the double bond .

Structural relatives

Structure of coniferyl aldehyde

One derivative is coniferylaldehyde [ 3- (4-hydroxy-3-methoxyphenyl) -2-propenal ], which on the benzene ring also carries a hydroxy group at the 4-position and a methoxy group at the 3-position , and thus the substitution pattern as in the case of vanillin .

Cinnamon alcohol	Cinnamaldehyde	Cinnamic acid

use

Cinnamaldehyde is used as a fragrance in perfume production in the composition of oriental perfumes. It is also used as a fragrance in cosmetics, e.g. B. in lipsticks, detergents, cleaning agents, toothpaste and mouthwash. It is also used as a spice in food.

In its pure form it has sensitizing properties and can lead to allergic skin reactions. Patients with a cinnamaldehyde allergy also often react to balsam of Peru , which indicates cross-allergies . The compound reacts with nucleophilic structural components of proteins , especially the thiol groups of cysteine , and can thus trigger a delayed-type immune reaction. Due to its high allergenic potential , it is part of the so-called "fragrance mix" for patch tests .

Web links

Commons : Cinnamaldehyde  - Collection of pictures, videos and audio files

• Entry to 2-propenal, 3-phenyl- . In: P. J. Linstrom, W. G. Mallard (Eds.): NIST Chemistry WebBook, NIST Standard Reference Database Number 69 . National Institute of Standards and Technology , Gaithersburg MD, accessed September 10, 2013.
• Fragrance Lexicon: Cinnamaldehyde

Individual evidence

1. ↑ ^{a b} Entry on FEMA 2286 in the database of the Flavor and Extract Manufacturers Association of the United States .
2. ↑ ^{a b c d e f g h i j k l} Entry on cinnamaldehyde in the GESTIS substance database of the IFA , accessed on January 10, 2017(JavaScript required) .
3. ↑ ^{a b c} Entry on cinnamaldehyde. In: Römpp Online . Georg Thieme Verlag, accessed on April 19, 2014.
4. ↑ ^{a b} data sheet trans-cinnamaldehyde (PDF) from Merck , accessed on September 10, 2013.
5. ↑ ^{a b c d} Committee for Hazardous Substances: Explanation on cinnamaldehyde in TRGS 907 - Edition: December 2011 - Status: May 2011 .
6. ↑ ^{a b} Dieter Martinetz, Roland Hartwig: Pocket book of fragrances: a lexicon from AZ . Harri Deutsch Verlag, 1998, ISBN 3-8171-1539-3 , p. 404 ( limited preview in Google Book Search).
7. ^ Albert Gossauer: Structure and Reactivity of Biomolecules , Verlag Helvetica Chimica Acta, Zurich 2006, ISBN 978-3-906390-29-1 , p. 313.
8. ^ Association of authors: Organikum , 19th edition, Johann Ambrosius Barth, Leipzig · Berlin · Heidelberg 1993, ISBN 3-335-00343-8 , p. 470.
9. ^ Association of authors: Organikum , 19th edition, Johann Ambrosius Barth, Leipzig · Berlin · Heidelberg 1993, ISBN 3-335-00343-8 , p. 345.
10. ^ Association of authors: Organikum , 19th edition, Johann Ambrosius Barth, Leipzig · Berlin · Heidelberg 1993, ISBN 3-335-00343-8 , p. 505.
11. ↑ Patent US3372199 : Method for the production of Process for the production of hydrocinnamaldehyde . Applied March 20, 1964 , published March 5, 1968 , Applicant: Engelhard Corporation , Inventor: Nathan Himselstein, Paul N. Rylander . ‌
12. ↑ Juliane Daphi-Weber, Heike Raddatz, Rainer Müller: Investigation of Fragrances - Controlled Fragrances , pp. 94–95, in Volume V of the series HighChem hautnah - News from food chemistry (published by the Society of German Chemists ) 2010, ISBN 978- 3-936028-64-5 .
13. ^ Jean-Marie Lachapelle: Patch Testing and Prick Testing. Springer Science & Business Media, 2012, ISBN 978-3-642-25492-5 , p. 108 ( limited preview in Google book search).
14. ↑ Axel Trautmann: Allergy Diagnosis Allergy Therapy. Thieme, 2006, ISBN 978-3-13-169061-6 ( limited preview in Google book search).