Ethyl 3-methyl-3-phenylglycidate

Description

Ethyl methylphenylglycidate is an aromatic organic compound with two functional groups, an ester and an epoxide. It is also known as “strawberry aldehyde” even though it is not found in strawberries and does not contain an aldehyde group. The compound contains two asymmetric centers; the article of commerce is a racemate of all four stereoisomers.
The first known synthesis of ethyl methylphenylglycidate was reported in 1905 by Rainer Ludwig Claisen at the University of Berlin in a lengthy article titled “About some syntheses using sodium amide”. Claisen was a pioneering chemist primarily known for developing condensation and rearrangement reactions that bear his name.
Today, ethyl methylphenylglycidate is synthesized by a method reported in 1961 by Keiiti Sisido, Osamu Nakanisi, and Hitosi Nozaki* at Kyoto University (Japan). They used the Darzens condensation, in which a ketone (acetophenone in this case) is treated with an α-haloester (ethyl chloroacetate) to form the epoxide ring.
Ethyl methylphenylglycidate’s flavor and aroma are reminiscent of strawberries, hence its nickname. It is used not only as an artificial strawberry-flavoring agent, but also in the fragrance industry, particularly in perfumes, personal care products, soaps, and detergents.
So why might you be consuming this molecule on Saturday? January 15 is National Strawberry Ice Cream Day! Be sure to get your fill of ethyl methylphenylglycidate.

Chemical properties

clear yellow liquid

Chemical properties

Ethyl 3-Methyl-3-phenylglycidate exists as two optically active pairs of cis- and trans-isomers; each isomer has a characteristic odor . The commercial product is a racemic mixture of all four isomers and has a strong, sweetish, strawberry odor. The cis/trans ratio obtained in the Darzens condensation of acetophenone (R==CH3) and ethyl chloroacetate depends on the base used in the reaction.

Chemical properties

Ethyl methylphenylglycidate on dilution has a strong fruity odor suggestive of strawberry. It has a characteristic, slightly acid taste reminiscent of strawberry.

Chemical properties

Perennial, herbaceous plant; grows wild or cultivated in central–southern Europe, North America and Asia. The plant grows 10 to 20 cm (4 to 8 in.) in height and has thick rhizomes; radical leaves with long, small, white flowers blossoming from April to July; and fleshy, ovoidal, red berries covered with numerous achenes. The only part used is the berries. Strawberry has a sweet–sour taste and a characteristic odor.

Occurrence

Has apparently not been reported to occur in nature.

The Uses of Ethyl 3-methyl-3-phenylglycidate

Ethyl 3-methyl-3-phenylglycidate is a synthetic flavoring agent that is a glycidic acid ester. It is a colorless to pale yellow liquid with a strong fruit odor suggestive of strawberries. It is unstable to alkali and moderately stable to weak organic acids. It should be stored in glass, tin, or aluminum containers. It is soluble in fixed oils and in propylene glycol. It is used in flavors for strawberry note and has application in candy, beverages, and ice cream at 6–20 ppm. It is also termed aldehyde c-16.

The Uses of Ethyl 3-methyl-3-phenylglycidate

Perfumery, flavors.

The Uses of Ethyl 3-methyl-3-phenylglycidate

Ethyl 3-Methyl-3-phenylglycidate, also known as “strawberry aldehyde”, is commonly used in the flavor industry for artificial fruit flavors, in particular strawberry.

Preparation

By reaction of acetophenone and the ethyl ester of monochloroacetic acid in the presence of an alkaline condensing agent.

Definition

ChEBI: Phenylmethylglycidic ester is a carboxylic acid and an epoxide.

Composition

Strawberry aroma has been the subject of extensive investigation. Several components have been identified, of which only 7% appear to be responsible for the aroma. Strawberry aroma varies widely with the strawberry variety. The most valuable part, aroma, is from wild strawberry.

Aroma threshold values

Detection: 2 ppm

Taste threshold values

Taste characteristics at 1 and 5% sucrose: sweet, ripe, strawberry jam and preserve notes.

Taste threshold values

Taste characteristics at 50 ppm: sweet, berry, strawberry, fruity, tutti-frutti and floral nuances

General Description

Clear, colorless to yellowish liquid with a strawberry-like odor.

Air & Water Reactions

Insoluble in water.

Reactivity Profile

Esters, such as Ethyl 3-methyl-3-phenylglycidate, react with acids to liberate heat along with alcohols and acids. Strong oxidizing acids may cause a vigorous reaction that is sufficiently exothermic to ignite the reaction products. Heat is also generated by the interaction of esters with caustic solutions. Flammable hydrogen is generated by mixing esters with alkali metals and hydrides.

Fire Hazard

Ethyl 3-methyl-3-phenylglycidate is probably combustible.

Trade name

Strawberry pure (Givaudan)

Safety Profile

Mddly toxic by ingestion. Mutation data reported. Combustible liquid. When heated to decomposition it emits acrid smoke and irritating fumes. See also ALDEHYDES.

Synthesis

Ethyl 3-methyl-3-phenylglycidate is synthesized by Acetophenone by condensation with Ethyl monochloroacetate in an alkaline solution, using sodium as a condensing agent.

Solubility in organics

Poorly soluble in Propylene glycol, Glycerin and mineral oil, soluble in alcohol, miscible with most perfume and flavor oils.