Benzylacetone: Properties, Applications, and Production Methods
Benzylacetone 2550-26-7
Benzylacetone (IUPAC name: 4-phenylbutan-2-one) is a liquid with a sweet floral odour and is considered to be the most abundant attractant compound in flowers (e.g., coyote tobacco, Nicotiana attenuata), and one of the volatile constituents of cocoa. It is used as a lure for melon flies (Bactrocera cucurbitae) and as an odourant in perfumes and soaps.
Chemical Properties of Benzyl Acetone
Appearance: colorless liquid. Sweet floral odor.
Solubility in water: slight
Melting point:-13°C
Boiling Point:235 °C(lit.)
Density:0.989 g/mL at 25 °C(lit.)
Vapor pressure:0.0386 hPa (20 °C)
Refractive index: n20/D 1.512(lit.)
Flash Point:209 °F
Storage condition:Sealed in dry,Room Temperature
Solubility:Chloroform, Methanol
Form:Liquid
Color:Clear colorless to pale yellow
Odor:at 100.00 %. floral balsam
Fragrance:Floral
Water solubility:PRACTICALLY INSOLUBLE
BRN:1907123
LogP:2 at 25℃
Chemical Properties
Colorless liquid. Boiling point 235℃, 115℃ (1.73kPa), relative density 0.985 (22/4℃), refractive index 1.511 (22℃), flash point 98℃.
Primary Aroma: Floral; Secondary Aroma: Green.
Fragrance Description: Often used in soap making, benzylacetone has a floral and sweet flavor that occurs naturally in cocoa and raspberries.
Natural Sources: Beef, Cocoa, Eggs, Blackberries, Water Yam.
Storage Methods
Keep container tightly sealed, place in tightly packed dispenser and store in a cool, dry place.
Uses
Benzyl Acetone is mainly used in the formulation of flavors and fragrances and pharmaceutical intermediates. The traditional production methods of Benzyl Acetone are as follows: (1) Benzyl chloride is obtained by condensation, hydrolysis and decarbonation; (2) Benzyl Acetone is synthesized from Benzaldehyde and Acetone, and then Benzyl Acetone is obtained by hydrogenation reduction. The traditional benzyl acetone production method has many steps, complicated process, large equipment and capital investment, and the production process produces a large amount of waste brine, which is difficult to deal with and brings great environmental protection pressure to the enterprise.
Benzylacetone (Benzylacetone) is one of the most commonly reported components of incense oil and extracts. There are many other phenolics in lesser quantities in incense oil, but this is one of the main ones. Curiously, according to The Good Scents Company, this compound has a strawberry flavor despite the balsamic aroma. It has been observed and reported to vary from 0.5% to 8% in incense oil and has been reported as one of its characteristic aroma-determining compounds.
Benzylacetone is suspected to be a “by-product” of another very important metabolic process in incense, leading to the production of a series of 2-phenylethylchromones. The vast majority of these heavier phenolic compounds are not volatilized into the essential oil, but small amounts of megapanax chromone (Flindersiachromone) are often found at the very end of the chromatogram. This group of chromones is very specific to incense and has attracted a great deal of research interest over the years due to some interesting biological properties.
Benzylacetone is released from heated sedum wood and is effective in reducing locomotor activity in mice when inhaled.
In the present study, the relationship between benzylacetone and its derivatives was investigated by comparing their sedative activities in mice and the chemical structures of these compounds.
The results show that benzylacetones have sedative activity, the strength of which varies depending on the functional groups on the carbon chain, the substituents on the benzene ring and their combinations.
The researchers conducted a quantitative structure-activity relationship study using a series of 17 benzylacetone derivatives to identify structural features that are important for sedative activity.
Usage
Used as intermediate for pharmaceutical synthesis
Fields of application
1. Present in cocoa as a volatile component.Used in the preparation of soap flavorings.Used in the preparation of soap flavors. Used as an attractant for melon flies.Used in chemical synthesis to prepare 4-oxocyclohexanecarboxaldehyde derivatives.
2. Flavor Industry:Acetophenone is an important fragrance ingredient widely used in perfumes, flavors and fragrances. It can give products a long-lasting fragrance and increase the layering and attractiveness of products.
3. Cosmetic Industry:In cosmetics, acetophenone is also often used as an ingredient in fragrances and flavorings. It imparts a pleasant odor to cosmetics and enhances product quality and market competitiveness.
4. Pharmaceutical field:Acetophenone and its derivatives are also used in the pharmaceutical field. It is used as an intermediate in organic synthesis for the preparation of a wide range of drugs and biologically active compounds, such as pharmaceutical raw materials and pharmaceutical intermediates.
5. Organic synthesis:Acetophenone has an important position in the field of organic synthesis, and it is an important synthesis intermediate for many organic compounds. Through the oxidation, reduction, hydroxylation and other reactions of acetophenone, a variety of organic compounds can be prepared, such as ketones, alcohols and ethers.
Preparation
Method 1: The synthesis method of benzyl acetone includes the following steps:
(1) Add aluminum trichloride (150 g, 1.1 mol), the first part of benzene (350 g) to a four-necked flask equipped with stirring, reflux condenser and thermometer, and stir well at a temperature of 30-35 °C;
(2) To the dropping funnel in step (1) was added a mixture of butenone (73 g, 1 mol) and the second part of the benzene (150 g), the reaction temperature was controlled at 30-35 ° C. After 2.5-3 hours of dropwise addition of the second part of the mixture of benzene and butenone, the reaction was continued for 0.5 hours, water was added to wash, and after the recovery of the benzene, the oil bath refining was carried out, and at a temperature of 80-85 ° C (50pa) Collected to get 99.95g; GC detection of benzyl acetone content of 98.97%, yield 66.84%.
Method 2: In the reaction vessel installed with stirrer, reflux condenser, dropping funnel, thermometer, add mass fraction of 60% cyclohexane 320 ml, add stannous chloride 1.3 mol in batches, add ethyl acetoacetate (1) 2.3 mol, control the stirring speed of 130 rpm, the reaction for 60 min, increase the temperature of the solution to 65 ° C, reflux for 3h, add benzyl amine (3) 2.6 mol dropwise. ) 2.6mol, dropwise addition of time control at 3h, reflux reaction 3h, the generation of intermediate products (4), reduce the solution temperature to 10 ℃, add 330ml mass fraction of 30% potassium bisulfite solution, keep refluxing for 4h, the generation of oily, add a mass fraction of 20% oxalic acid to adjust the solution pH to 4, continue to reflux for 4h, 1.13kPa decompression distillation, collection of 95— 105 ℃ fraction, sodium nitrate solution wash, mass fraction of 70% acetonitrile wash, in the mass fraction of 90% nitromethane in the recrystallization, get crystal benzyl acetone 241.68g, yield 71%.
Production method
The main production methods of acetophenone include etherification of aromatic hydrocarbons with ketones, acylation reduction and alcohol-acid esterification. Among them, the etherification reaction of aromatic hydrocarbons with ketones is one of the most commonly used industrial production methods. The reaction is usually carried out under alkaline conditions, and acetophenone can be prepared by selective oxidation, reduction or hydroxylation of acetophenone precursors.
(1) Obtained from benzyl chloride by condensation, hydrolysis and decarbonation. (2) Benzylacetone is synthesized from benzaldehyde and acetone, and then 4-phenylbutanone-2 is obtained by hydrogenation and reduction. 4-phenylbutanone-2 is prepared by putting ethanol (95% 1100 ml), benzylacetone (480 g), Raney Ni (48 g), and acetic acid into the reaction flask, and then controlling the temperature at 48-50°C, stirring and absorbing the hydrogen at atmospheric pressure until the amount is enough. Reaction 4-5h. filtered off Raney Ni. filtrate evaporated ethanol, distillation under reduced pressure, collection of 123-125 ℃ (2.67kPa) fraction, obtained 4-phenylbutanone-2 for 465.8g. refractive index 1.513, yield 95.7%.
Synthesis method
Acetophenone can be prepared by selective hydrogenation of benzylidene acetone (prepared from benzaldehyde and acetone).
Obtained from benzyl chloride by condensation, hydrolysis and decarbonation. Benzylidene acetone was synthesized from benzaldehyde and acetone, and then 4-phenylbutanone-2 was obtained by hydrogenation and reduction. 4-phenylbutanone-2 was prepared by putting ethanol (95% 1100 ml), benzylidene acetone (480 g), Raney Ni (48 g), and acetic acid into the reaction flask, and then controlling the temperature at 48-50 ℃, stirring and absorbing the hydrogen at atmospheric pressure until the amount was sufficient. Reaction 4-5h. filtered Raney Ni. filtrate evaporated ethanol, distillation under reduced pressure, collect 123-125 ℃ (2.67kPa) fraction, get 4-phenylbutanone-2 for 465.8g. refractive index 1.513, yield 95.7%.
(2) Preparation method:
Referring to the preparation method of phenylacetone, 100g (0.66mol) of phenylpropanoic acid, 160g (2.66mol) of glacial acetic acid were used for the reaction, extracted with ether and then distilled, and the fractions were collected from 230 to 235°C, yielding 4-phenyl-2-butanone as 70g with 71% yield. Pure 4-phenyl-2-butanone bp234°C.
First Aid
Indigestion: Seek medical assistance. Rinse mouth with water.
INHALATION: Remove to fresh air immediately.
Skin: Flush skin with plenty of soap and water for at least 15 minutes and remove contaminated clothing and shoes.
EYES: Flush eyes with plenty of water for at least 15 minutes, occasionally lifting upper and lower eyelids. Seek medical attention.
Handling and Storage
STORAGE: Store in a cool, dry place. Store in airtight container.
HANDLING: Avoid breathing dust, vapors, mists or gases. Avoid contact with skin and eyes.
Hazard Identification
DIGESTION: May be harmful if swallowed.
INHALATION: May irritate respiratory tract. May be harmful if inhaled.
SKIN: Causes severe skin irritation. May be harmful if absorbed through skin.
Eyes: May irritate eyes.
EC Risk Words: R 36/38
EU Safety Phrase: S 26 36
Exposure control/personal protection
PERSONAL PROTECTION: SKIN: Wear suitable protective gloves to prevent skin contact. Clothing: Wear chemical apron.
RESPIRATORS: Comply with OSHA Respirator Regulation 29CFR 1910.134 or European Standard EN 149. Always use NIOSH or European Standard EN 149 approved respirators when necessary.
Fire Fighting Measures
Ignition point: >100
FIRE FIGHTING: Wear pressure-demand self-contained breathing apparatus (SCBA), MSHA/NIOSH (approved or equivalent), and full protective equipment. Extinguish fire with water spray, dry chemical, carbon dioxide or chemical foam.
Accidental Release Measures
Small spills/leaks: absorb spill with inert material (e.g., dry sand or dirt) and place in chemical waste container.
Safety Information
Hazard symbol: Xi
Hazard Class Code: 38
Safety instructions: 37-24/25
WGK Germany: 1
RTECS number: EL9600000
TSCA: Yes
Customs code: 29143900
Toxicity: LD50 orally in Rabbit: 3200 mg/kg
Safety Data
Acetophenone may cause skin irritation, severe eye irritation, and hazards if swallowed according to GHS classification. Appropriate precautions should be taken, such as wearing protective eyewear and gloves.
Environmental Effects
May release irritating fumes and gases when heated to decomposition.
Medical Studies
Acetophenone shows potential inhibition of mushroom tyrosinase and may have applications in appetite enhancement and exercise reduction.
Safety and environmental effects
Acetophenone is relatively safe for humans under normal conditions of use, but prolonged exposure may have negative health effects. Appropriate protective measures should be taken to avoid skin contact and inhalation of gas during production and use. In addition, the production and handling of acetophenone should be strictly controlled to minimize the impact on the environment.
Reactions
Like most methyl ketone compounds, benzylideneacetone is a mildly acidic compound at the alpha position and can be deprotonated very easily to give the corresponding enol compound. The compound can undergo the following reactions due to the presence of the following functional groups, e.g.: addition of double bonds to bromine; Diels-Alder reaction of heterodiene compounds to olefins to give dihydropyran compounds; methyl groups can be further condensed with benzaldehyde to give dibenzylidene acetone; and the carbonyl groups can form hydrazones. The compound can also react with Fe2(CO)9 to give (benzylideneacetone)Fe(CO)3, a reagent that can deliver Fe(CO)3 to other organic chemical substrates.
