Phenylacetaldehyd Chemische Eigenschaften,Einsatz,Produktion Methoden
R-Sätze Betriebsanweisung:
R22:Gesundheitsschädlich beim Verschlucken.
R36/37/38:Reizt die Augen, die Atmungsorgane und die Haut.
R43:Sensibilisierung durch Hautkontakt möglich.
R11:Leichtentzündlich.
S-Sätze Betriebsanweisung:
S26:Bei Berührung mit den Augen sofort gründlich mit Wasser abspülen und Arzt konsultieren.
S36:DE: Bei der Arbeit geeignete Schutzkleidung tragen.
S37:Geeignete Schutzhandschuhe tragen.
S24:Berührung mit der Haut vermeiden.
S16:Von Zündquellen fernhalten - Nicht rauchen.
S7:Behälter dicht geschlossen halten.
Beschreibung
Phenylacetaldehyde is an organic compound which can be naturally found in buckwheat, flowers, and communication pheromones from various insect orders. It is commonly used for the preparation of fragrance as well as flavors, and applied in flavored cigarettes and beverages because of its honey-like sweet character. It is also applied in the synthesis of polymers, such as polyesters, as a rate controlling additive in polymerization reactions and used in the preparation of more complex chemicals like resmethrin, where it acts as a building block.
Chemische Eigenschaften
Phenylacetaldehyde has a harsh, green odor reminiscent of hyacinth on dilution. It has an unpleasant, pungent, bitter flavor, turning sweet and fruit-like at low levels. Since it readily undergoes oxidation and polymerizes, it must be stabilized by addition of antioxidants and by dilution with, for example, diethyl phthalate before use in compositions.
Occurrence
Identified among the constituents of several essential oils: neroli, Citrus sinensis leaves, other citrus species
(flowers and leaves), narcissus, magnolia, lily, rose and tea. It is reported found in over 170 natural products including apricot,
sour cherry, cooked apple, peach, fresh blackberry, crispbread, other types of bread, green tea, unprocessed rice, lemon balm, red
sage, black currant, bilberry, cranberry, other berries, grapes, raisins, melon, papaya, guava fruit, pineapple, asparagus, celery
leaves, carrot, parsley, peas, bell pepper, sweet pepper, peach, cabbage, peppermint oil, Scotch spearmint oil, mustard, vinegar,
onion, cooked potato, tomato, cinnamon bark, cassia leaf, ginger, many cheeses, milk, yogurt, boiled egg, cooked and cured
meats, beer, cognac, grape wines, cocoa, coffee, tea, roasted filbert, roasted peanut, soybean, pecans, cauliflower, broccoli, honey,
avocado, passion fruit, beans, mushrooms, trassi, mango, tamarind, rice, licorice, buckwheat, lovage root, pumpkin, sweet potato,
cassava, corn oil, malt, wort, dried bonito, loquat, pawpaw, maté, sweet grass oil, orange peel oil, grapefruit juice, endive, clam
and Chinese quince.
Verwenden
Phenylacetaldehyde is used for the preparation of fragrances and polymers like polyesters, which find application as a rate controlling additive in polymerization reactions. It is an active component of fragrances and floral scent due to its honey-like sweet character and finds application in flavored cigarettes and beverages. It is an insect attractant and utilized in blacklight trap for pests. It is also used as a building block in the synthesis of more complex chemicals, such as resmethrin. Furthermore, it is used in association with acetic anhydride and allyltrimethylsilane in three-component coupling process catalyzed by LiBF4 providing homoallylic acetates.
Definition
ChEBI: Phenylacetaldehyde is an aldehyde that consists of acetaldehyde bearing a methyl substituent; the parent member of the phenylacetaldehyde class of compounds. It has a role as a human metabolite, a Saccharomyces cerevisiae metabolite, an Escherichia coli metabolite and a mouse metabolite. It is an alpha-CH2-containing aldehyde and a member of phenylacetaldehydes.
Allgemeine Beschreibung
Phenylacetaldehyde is an important aroma volatile found in tomato and roses. It has also been identified in potato, roasted cocoa beans and honey. Phenylacetaldehyde is also a potent moth attractant.
Sicherheitsprofil
Moderately toxic by
ingestion. Human skin irritant. Combustible
liquid. When heated to decomposition it
emits acrid smoke and irritating fumes. See
also ALDEHYDES.
Synthese
Phenylacetaldehyde can be synthesized by Darzen glycidic ester synthesis from benzaldehyde; readily oxidizable to phenyl acetic acid.
Vorbereitung Methode
The most important method industrially is the isomerization of styrene oxide. Ion-exchange resins, catalysis by chromium trioxide–tungsten trioxide on graphite or silicon dioxide–aluminum trioxide, and thermolysis are recommended for the rearrangement. Phenylacetaldehyde can also be synthesized by the direct oxidation of styrene in the presence of palladium salts and copper(II) chloride in aqueous solutions of glycol ethers. Other possibilities include the catalytic dehydrogenation of 2-phenylethanol on silver or gold catalysts, the hydroformylation of benzyl halides in the presence of dicobalt octacarbonyl and sodium carbonate in acetonitrile, and the Darzens glycide ester synthesis from benzaldehyde and alkyl chloroacetates.
Phenylacetaldehyd Upstream-Materialien And Downstream Produkte
Upstream-Materialien
Downstream Produkte
