4'-Methoxyacetophenone

Identification

Description

Yellowish-white crystals with an odor similar to that of p-methylacetopheneone, suggestive of hawthorn and floral note of heliotrope, possessing a bitter and unpleasant taste. Useful in vanilla, nut, tobacco and butter flavors.

Regulatory Status

CoE: Approved. Bev.: 10 ppm; Food: 20 ppm
FDA: 21 CFR 172.515
FDA (other): n/a
JECFA: ADI: Acceptable. No safety concern at current levels of intake when used as a flavoring agent (2001).

Usage

Reported uses (ppm): (FEMA, 1994)

Natural occurrence

Reported found in European cranberry (Vaccinium oxycoccus L.), guava fruit (Psidium guajava L.), Vitis labrusca L., tomato, anise (Pimpinella anisum L.), mentha oils, grilled and roasted beef, sherry, cloudberry (Rubus chamaemorus L.), salted and pickled plums, Illicium verum and black chokeberry (Aronia melanocarpa ell.).

Chemical Properties

4-Methoxyacetophenone occurs in anise oil. It forms white crystals (mp 38°C) with a sweet odor, reminiscent of hawthorn. 4-Methoxyacetophenone is prepared by Friedel–Crafts acetylation of anisole. A modern process uses -zeolites as Friedel–Crafts catalysts in combination with a continuous flow technology. 4-Methoxyacetophenone is used in soap perfumes

Chemical Properties

WHITE CRYSTALS OR CRYSTALLINE POWDER

Chemical Properties

Colorless crystals or fused crystalline/Yellowish-white crystals mass. with an odor similar to that of p-methylacetopheneone, suggestive of hawthorn and floral note of heliotrope, possessing a bitter and unpleasant taste. Useful in vanilla, nut, tobacco and butter flavors. Heavier than water, practically insoluble in water. Miscible with oils, soluble in alcohol, Relatively stable in soap and under similar, mild-alkaline conditions.

Occurrence

Reported found in European cranberry (Vaccinium oxycoccus L.), guava fruit (Psidium guajava L.), Vitis labrusca L., tomato, anise (Pimpinella anisum L.), mentha oils, grilled and roasted beef, sherry, cloudberry (Rubus chamaemorus L.), salted and pickled plums, Illicium verum and black chokeberry (Aronia melanocarpa ell.).

Uses

4'-Methoxyacetophenone is used as a component of perfumes and as chemical intermediate in the manufacture of pharmaceuticals, resins, flavouring agents. And also used to study ruthenium catalyzed step growth copolymerization of 4-methoxyacetophenone with α,ω-dienes to yield copolymers.

Uses

4'-Methoxyacetophenone is a solid, pale yellow flavoring agent with a hawthornlike odor. It is soluble in most fixed oils and propylene glycol, and it is insoluble in glycerin and mineral oil. It is obtained by chemical synthesis. This flavoring substance or its adjuvant may be safely used in food in the minimum quantity required to produce its intended flavor. It can be used alone or in combination with other flavoring substances or adjuvants. It is also termed p-methoxyacetophenone.

Uses

Perfumery (for floral odors), flavoring.

Definition

ChEBI: A member of the class of acetophenones that is acetophenone substituted by a methoxy group at position 4.

Preparation

From anisole and acetyl chloride in the presence of aluminum chloride and carbon disulfide; from anisole and acetic acid in the presence of boron trifluoride.

Taste threshold values

Taste characteristics at 10 ppm: sweet, anisic, fruity, cherry with powdery vanilla nuances.

Synthesis Reference(s)

The Journal of Organic Chemistry, 46, p. 5414, 1981 DOI: 10.1021/jo00339a036
Synthetic Communications, 26, p. 291, 1996 DOI: 10.1080/00397919608003617
Tetrahedron Letters, 35, p. 9471, 1994 DOI: 10.1016/S0040-4039(00)78574-1

General Description

4′-Methoxyacetophenone undergoes biocatalytic enantioselective reduction using immobilized Rhodotorula sp. AS2.2241 cells to yield (S)-1-(4-methoxyphenyl) ethanol in a hydrophilic ionic liquid-containing co-solvent system.

Flammability and Explosibility

Not classified

Safety Profile

Moderately toxic by ingestion. Human systemic effects by inhalation: pulse rate increase without fall in blood pressure and blood pressure elevation. A skin irritant. Flammable liquid. When heated to decomposition it emits acrid smoke and irritating fumes. See also KETONES.

Purification Methods

Crystallise the ketone from diethyl ether/pet ether. [Beilstein 8 IV 340.]

Toxics Screening Level

The ITSL for 4-methoxyacetophenone has been changed from 0.04 μg/m3 to 0.1 μg/m3 based on an annual averaging time.