Background and overview[1]
Phenethyl acetate is a colorless liquid; it has a floral aroma similar to roses with a honey-like undertone, and a sweet fruit-like taste like strawberry; boiling point 232℃; flash point 105℃; density D25251.030 ~1.034; refractive index nD201.4970~1.5010; acid value not exceeding 1; soluble in 70% ethanol at 1:2 or above, and soluble in most common organic solvents. Phenethyl acetate is a commonly used synthetic spice, which has been widely used in the preparation of rose, orange blossom, violet, wild rose and fruity spices. It is also an edible spice allowed by my country’s GB2/60-86. Strong acid catalysts such as sulfuric acid and phosphoric acid are commonly used in the preparation of phenethyl acetate. This not only results in low product quality due to many side reactions, but also causes serious equipment corrosion. Therefore, it is of great practical significance to develop a green, efficient and environmentally friendly synthesis method of phenethyl acetate. Since the price of phenylethyl alcohol, the raw material used in the synthesis of esterification method, is also high, the price of acetic anhydride is also high and the state control is very strict, while the price of acetic acid is low, so the synthesis route of the reaction of acetic acid and phenylethyl alcohol is mostly used in production. Because esterification is a reversible reaction, the yield is not high, and acidic wastewater will be produced after the reaction is completed, which can easily cause environmental problems.
Purpose[2-3]
Phenethyl acetate can be used in the preparation of soaps and daily cosmetic fragrances, and can be used as a substitute for methyl enanthate. It is often used to prepare rose, orange blossom, briar and other flavors, as well as fruit flavors (with peach aroma).
1) Prepare a honey flavor with natural honey flavor, which is composed of linalool oxide, triacetin, ethanol, propylene glycol, phenethyl alcohol, turconenone, ethyl maltol, and honey aroma base. It is turconenone, rose geranium oil, 4-hydroxy-2,5-dimethyl-3(2H) furanone, triethyl citrate, methyl anthranilate, vanillin, caproic acid, nonyl A combination of acid, 2-acetylfuran, 2-methylbutyric acid, α-terpineol, butyric acid, benzaldehyde, phenethyl phenylacetate, phenethyl acetate, phenethyl butyrate, and propylene glycol, Propylene glycol and ethyl maltol are mixed and heated to dissolve and then cooled to room temperature. Triacetin, ethanol, linalool oxide, phenethyl alcohol, turconenone, and honey aroma base are added to obtain a product. The honey flavor has a better honey-sweet flavor. .
2) Prepare a coffee bean elephant attractant. Coffee bean elephant attractants include benzyl alcohol, 2-phenylethyl alcohol, benzyl acetate, and phenethyl acetate. The weight percentage of each component in the coffee bean elephant attractant is: benzyl alcohol-3-15-%, 2-phenylethyl alcohol-30-42-%, benzyl acetate-15-20-%, phenethyl acetate -32-43-%. The attractant ingredients of the present invention are mostly microbial secondary metabolites, have simple structure, wide sources, low price, simple and convenient preparation method of the lure core, simple use method, low labor intensity, and the trap containing the lure core can be directly hung and placed on Above storage objects, it is extremely suitable for pest control in storage environments.
Preparation method
A method for synthesizing phenethyl acetate, characterized in that the method includes the following steps:
Step 1. Add 100g phenylethyl alcohol, 200ml dichloroethane, and Pt/Si02g catalyst into a 500ml four-necked flask equipped with a mechanical stirring rod, a reflux condenser, and a constant pressure funnel. Add 55g acetic anhydride slowly and dropwise while stirring. Heating and refluxing for 1 hour;
Step 2. Change the reflux device to a distillation device and steam out part of the dichloroethane until the distillate is clear and the distilled volume is 100ml;
Step 3. Cool the reaction solution to below 10°C, wash with ice water to obtain a solution of phenethyl acetate in dichloroethane, dry it over anhydrous magnesium sulfate, and distill the dichloroethane completely under reduced pressure to obtain Phenethyl acetate.
The preparation method of the Pt/Si0 catalyst is as follows:
Step 1. Fully dissolve and disperse 3g NaSiO·9H0 into water, then slowly add 10g of ethyl acetate dropwise, and continue stirring for 1 hour to complete the reaction;
Step 2: Aging the above solution in the air for 24 hours, filtering, washing with secondary water several times, vacuum drying at 40°C, and drying for 6 hours to obtain SiO nanoparticles;
Step 3: Disperse 2mgSi0 in 5mL of water, add 1wt% hydrofluoric acid to etch for 1min, then add 1.33ml of 38.62mM HPtCl, and oscillate ultrasonic for 30min;
Step 4. Add 3ml of 40mM NaBH reducing agent to the above mixture, continue ultrasonic shaking for 2 hours until the remaining NaBH is fully decomposed, and centrifuge and wash until PH=7;
Step 5: Put the above centrifuged product into a vacuum drying oven at 40°C and dry it for 8 hours to obtain a Pt/Si0 nanocatalyst.
Main reference materials
[1] Synthetic fragrance product technical manual
[2] CN201410775113.9 Honey essence and preparation method thereof
[3] CN201610554807.9 A coffee bean elephant attractant and its application
[4] CN201810745701.6 A synthesis method of phenethyl acetate
