Cinnamic acid

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Cinnamic acid

General
Systematic name	(E)-3-phenyl-2-propenoic acid
Other names	Cinnamic Acid
Molecular formula	C₆H₅CHCHCOOH
Molar mass	148.17 g/mol
Appearance	monoclinic crystals
CAS number	[140-10-3]
Properties
Solubility in water	0.4 g/L
Solubility in	Ethanol, Acetone, THF
Density	1.2475 g/cm³
Melting point	135-136 °C
Boiling point	300 °C
Hazards
MSDS	External MSDS (pdf)
EU classification	Irritant (Xi)
R-phrases	R36
S-phrases	S25
Flash point	>110 °C
LD₅₀ oral, rat	2500 mg/kg
LD₅₀ dermal, rabbit	>5000 mg/kg
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox disclaimer and references

Cinnamic acid has the formula C₆H₅CHCHCOOH and is an odorless white crystalline acid, which is slightly soluble in water. It has a melting point of 133°C and a boiling point of 300°C.

It is obtained from oil of cinnamon, or from balsams such as storax. It is also found in shea butter and is the best indication of its environmental history and post-extraction conditions. It can also be made synthetically.

Cinnamic acid is used in flavours, synthetic indigo, and certain pharmaceuticals, though its primary use is in the manufacturing of the methyl, ethyl, and benzyl esters for the perfume industry. Cinnamic acid has a "honey, floral odor" (Merck Index); it and its more volatile ethyl ester (ethyl cinnamate) are flavour components in the essential oil of cinnamon, in which related cinnamaldehyde is the major constituent. Cinnamic acid is also part of the biosynthetic shikimate and phenylpropanoid pathways. Its biosynthesis is performed by action of the enzyme phenylalanine ammonia lysase (PAL) on phenylalanine.

Cinnamic acid is soluble in diethyl ether, insoluble in hexane.

[edit] References

Flavornet.org
CRC Handbook
Chemfinder
Katzer, G. Gernot Katzer's Spice Pages, accessed August 17, 2006.
Budavari, Susan (Ed.) The Merck Index, 13 Ed. Merck & Co., Inc, Whitehouse Sta-

tion, NJ, USA, 2001.