Uses
o-Methoxycinnamaldehyde is a food flavoring permitted for use according to GB2760-1997.
Description
o-Methoxycinnamaldehyde has a sweet, warm, spicy-floral odor
with fruity undertones. It has a sweet, spicy, warm flavor, somewhat pungent above 200 - 300 ppm. It is formed after a long
contact period between salicylaldehyde and acetaldehyde in
diluted alkaline solution; it can be formed by condensation of
salicylaldehyde methylether with acetaldehyde under alkaline conditions; from the corresponding oxime.
Chemical Properties
o-Methoxycinnamaldehyde has a sweet, warm, spicy-floral odor with fruity undernotes. It has a sweet, spicy, warm
flavor and is somewhat pungent above 200 to 300ppm.
Occurrence
Reported found in cinnamon oil (Cinnamomum cassia Nees ex Bl.) from which it is separated as stearoptene;
in cinnamon bark and leaf.
Preparation
It is formed after a long contact period between salicylaldehyde and acetaldehyde in diluted alkaline solution; it may
also be formed by condensation of salicylaldehyde methylether with acetaldehyde under alkaline conditions; from the corresponding
oxime. It may be isolated and purified from powdered cinnamon.
Definition
ChEBI: Cassiastearoptene is a member of cinnamaldehydes.
Taste threshold values
Taste characteristics at 50 ppm: warm, spicy, cinnamon and clove-like.
General Description
Yellow crystals.
Air & Water Reactions
Insoluble in water.
Reactivity Profile
Aldehydes, such as 2'-Methoxycinnamaldehyde, are frequently involved in self-condensation or polymerization reactions. These reactions are exothermic; they are often catalyzed by acid. Aldehydes are readily oxidized to give carboxylic acids. Flammable and/or toxic gases are generated by the combination of aldehydes with azo, diazo compounds, dithiocarbamates, nitrides, and strong reducing agents. Aldehydes can react with air to give first peroxo acids, and ultimately carboxylic acids. These autoxidation reactions are activated by light, catalyzed by salts of transition metals, and are autocatalytic (catalyzed by the products of the reaction). The addition of stabilizers (antioxidants) to shipments of aldehydes retards autoxidation.
Fire Hazard
2'-Methoxycinnamaldehyde is flammable.
Synthesis
The general procedure for the synthesis of 2'-methoxycinnamaldehyde from the compound (CAS:1504-61-6) is as follows: alcohol (5.0 mmol), copper acetate (Cu(OAc)2, 9.1 mg, 0.05 mmol), and TEMPO (7.8 mg, 0.05 mmol) were mixed in a mixture of acetonitrile (CH3CN, 5 mL) and water (H2O, 10 mL) in a mixed solvents at room temperature with stirring for the indicated times. The progress of the reaction was monitored by thin-layer chromatography (TLC) with the eluent ratio of petroleum ether/ethyl acetate = 4/1. After completion of the reaction, the reaction mixture was extracted by adding dichloromethane (10 mL) to the reaction mixture. The organic phase was separated and the aqueous phase was extracted twice more with dichloromethane (10 mL x 2). All organic layers were combined, dried with anhydrous sodium sulfate and concentrated to obtain the crude product. The crude product was purified by column chromatography with the eluent ratio of petroleum ether/ethyl acetate=10/1, and the target product 2'-methoxycinnamaldehyde was finally obtained.
References
[1] Tetrahedron Letters, 2014, vol. 55, # 10, p. 1677 - 1681
[2] European Journal of Organic Chemistry, 2016, vol. 2016, # 20, p. 3401 - 3407
[3] Bioorganic and Medicinal Chemistry Letters, 1997, vol. 7, # 19, p. 2473 - 2476
