4'-метилацетофенон

Описание

4'-Methylacetophenone has a fruity, floral odor resembling acetophenone and a sweet, strawberry-like flavor. May be prepared by slow addition of acetyl chloride to a mixture of toluene and AlCl in an ice bath and under vacuum, maintaining the temperature at +5°C and then letting it increase to +20°C.

Химические свойства

4'-Methylacetophenone has been identified in Brazilian rosewood oil and in pepper. It occurs as colorless crystals with a floral, sweet odor that is milder than that of acetophenone. 4-Methylacetophenone is prepared from toluene and acetic anhydride or acetyl chloride by a Friedel–Crafts reaction. It is used for blossom notes in mimosaand hawthorn-type perfumes, especially soap perfumes.

Вхождение

Reported found in the essential oil distilled from the wood of Myrocarpus fastigiatus, Myrocarpus frondo sus, Bois de Rose. Also reported found in sour cherry, orange and grapefruit peel oil, black currants, guava, peach, blackberry, celery, potato, tomato, mentha oils, pepper, parsley, smoked fish, cognac, parmesan cheese, cocoa, tea, soybean, cloudberry, mango, cauliflower, broccoli, rice bran, buckwheat, dried bonito, cherimoya, calabash nutmeg and mastic gum leaf oil, cooked cabbage, mandarin juice.

Использование

4'-Methylacetophenone is a methylated acteophenone used in cosmetics and perfumery. The presence of 4'-Methylacetophenone has been shown to accelerate the photopolymerization of Methyl methacrylate.

Подготовка

By slow addition of acetyl chloride to a mixture of toluene and AlCl in an ice bath and under vacuum, maintaining the temperature at +5°C and then letting it increase to +20°C.

Определение

ChEBI: 4'-Methylacetophenone is an aromatic ketone. It is a metabolite found in or produced by Saccharomyces cerevisiae.

Общее описание

4′-Methylacetophenone is a clear colourless to pale yellowish liquid that occurs naturally in mango, tomato and orange.

Профиль безопасности

Moderately toxic by ingestion. A human skin irritant. A flammable liquid. When heated to decomposition it emits acrid smoke and irritating fumes. See also KETONES.

Методы очистки

Impurities, including the o-and m-isomers, are removed by forming the semicarbazone (m 212-213.5o) which, after repeated crystallisation, is hydrolysed to the ketone. [Brown & Marino J Am Chem Soc 84 1236 1962.] It can also be purified by distillation under reduced pressure, followed by low temperature crystallisation from isopentane. [Beilstein 7 IV 701.]