6-Methyl-5-hepten-2-one 6-Methyl-5-hepten-2-one
Structural formula
| Business number | 032E |
|---|---|
| Molecular formula | C8H14O |
| Molecular weight | 126.20 |
| label |
Methylheptenone, 2-Methyl-6-oxo-2-heptene, Methyl heptenone, 2-Methyl-2-hepten-6-one, Fragrance |
Numbering system
CAS number:110-93-0
MDL number:MFCD00008905
EINECS number:203-816-7
RTECS number:MJ9700000
BRN number:1741705
PubChem number:24901275
Physical property data
1. Properties: colorless or light yellow liquid with aroma like lemongrass and isobutyl acetate.
2. Melting point (ºC): -67.1
3. Boiling point (ºC): 73 (2399pa)
4. Relative density (d 164) : 0.8546
5. Refractive index (n20D): 1.4445
6. Flash point ºC): 50
7. Solubility: Insoluble in water, miscible with alcohol and ether.
Toxicological data
1. Acute toxicity: Rat oral LD50: 3500mg/kg
Rabbit transdermal LD50: >5000mg/kg
Rat transdermal LD50: >2000mg/kg
Mouse oral LD5O: 2410mg/kg
Ecological data
This substance is slightly hazardous to water.
Molecular structure data
1. Molar refractive index: 39.04
2. Molar volume (cm3/mol): 151.1
3. Isotonic specific volume (90.2K ): 338.8
4. Surface tension (dyne/cm): 25.2
5. Polarizability (10-24cm3): 15.47
Compute chemical data
1. Reference value for hydrophobic parameter calculation (XlogP): None
2. Number of hydrogen bond donors: 0
3. Number of hydrogen bond acceptors: 1
4. Number of rotatable chemical bonds: 3
5. Number of tautomers: 3
6. Topological molecule polar surface area 17.1
7. Number of heavy atoms: 9
8. Surface charge: 0
9. Complexity: 119
10. Number of isotope atoms: 0
11. Determine the number of atomic stereocenters: 0
12. Uncertain number of atomic stereocenters: 0
13. Determine the number of chemical bond stereocenters: 0
14. Number of uncertain chemical bond stereocenters: 0
15. Number of covalent bond units: 1
Properties and stability
1. �It does not decompose under normal temperature and pressure. Contact with strong oxidants is prohibited.
2. Naturally found in guava, tomatoes, and ginger.
3. Found in flue-cured tobacco leaves, burley tobacco leaves, and oriental tobacco leaves.
Storage method
Store in a cool, ventilated warehouse. Keep away from fire and anti-static. The storage temperature should not exceed 30℃. Keep container tightly sealed. should be kept away from oxidizer, do not store together. It should not be stored in large quantities or for long periods of time. Use explosion-proof lighting and ventilation facilities. It is prohibited to use mechanical equipment and tools that are prone to sparks. The storage area should be equipped with emergency release equipment and suitable containment materials.
Synthesis method
1. Acetylene acetone method: Using acetylene and acetone as raw materials, methyl butynol is first produced. The latter is reduced to enol and reacts with ethyl acetoacetate or diketene to obtain methyl heptenone.
2. Isobutylene method uses isobutylene as raw material, synthesizes α-methylheptenone with acetone and formaldehyde at 250℃ and 30MPa in one step, and then heats and converts it under the action of palladium and carbonyl iron catalyst to obtain methane. Heptenone. Methyl heptenone is synthesized in one step using isobutylene, acetone and formaldehyde as raw materials. Under the reaction conditions of reaction pressure 30MPa, reaction temperature 310~320°C, isobutylene:acetone:formaldehyde 5:4:1 (molar ratio), and reaction residence time 115h, the yield of methylheptenone reached 34% ( Based on the feed formaldehyde), the space-time yield reaches 35g/(h·L). Research results show that adding phosphoric acid or caustic soda cannot play a catalytic role. The lower the reaction temperature, the higher the ratio of α-methylheptenone to β-methylheptenone. Since this process is a condensation reaction between three molecules, there are many side reactions and the requirements for product separation and purification are high.
3. Isoprene method This method was first proposed by the French company Rhodia. It uses isoprene as raw material and reacts with hydrochloric acid to generate isoprene chloride. The latter reacts with acetone to produce the product, which is The batch reaction process is carried out in an anhydrous system. Currently, the Rhodia method has been discontinued. Japan’s Kuraray Company has improved this process, using quaternary ammonium salts as phase transfer catalysts to carry out continuous reactions in sodium hydroxide aqueous solutions. The company has built production equipment.
4. Tobacco: BU, 56; BU, 14; OR, 57; FC, 9, 18, 40; BU, OR, 18.
Purpose
1. Mainly used to prepare banana, pear, citrus and berry flavors. But it is rarely used directly as a spice, but as a raw material for synthetic spices. For example, it is used to synthesize pseudoionone and citral. Also used in other organic synthesis.
2. Used in baked goods, meat, sugar, and beverages.