Chinese aliases: linalool, linalool, linalool, coriander, agarwood terpene alcohol, Galol, coriander alcohol, 3.7- dimethyl-1, 6- octadiene -3- alcohol, linalool.
English alias linalool, 3.7- dimethyl-1, 6- octadiene -3- alcohol, 2,6- dimethyl-2,7-octadiene -6- alcohol.
The molecular formula (CH3) 2cchch2c (CH3) (OH) chch2? C 10H 18O
Molecular weight 154.25
CASNo. 78-70-6
MDL:MFCD00008906
Smile: C=CC(CCC=C(C)C)(O)C
EINECS:20 1- 134-4
It has the commonness and characteristics of alcohols and olefins, such as esterification and dehydration, and can be easily reduced to corresponding hydrocarbons. In the presence of metallic sodium, dihydromyrcene is generated. When reduced on colloidal platinum or skeleton nickel, dihydrolinalool and tetrahydrolinalool are produced.
The vinyl ether generated by the reaction of linalool and ethyl vinyl ether was rearranged by Claisen to obtain R, δ-unsaturated aldehyde, which had the fragrance of oleoaldehyde and floral fragrance after dilution. Used to prepare rosewood oil, moonlight essence and jasmine essence. The product was condensed with acetone under the catalysis of zinc acetate, and then cyclized under the action of phosphoric acid to obtain 1. 1-2 methyl -7- acetonyl-octahydronaphthalene, which is a new perfume.
Geranyl isobutyraldehyde can be obtained by the reaction of linalool with isobutyraldehyde in the presence of acidic catalyst. Aroma raw materials have strong floral and fragrant fragrance. After hydrogenation, the corresponding alcohol can be obtained, which has quite elegant floral and woody fragrance. Further development, cyclization reaction was carried out in the presence of BF3, Et2O, H3PO4 and trifluoroacetic acid to obtain monocyclic and bicyclic ethers with beautiful fragrance.
However, the condensation and cyclization products of geranyl isobutyraldehyde and acetone have a lasting Long Xianxiang flavor. The adduct of linalool and ethyl vinyl ether in the presence of phosphoric acid is mixed acetal. Mixed acetals produced by dihydrolinalool and ethyl vinyl ether are very useful spices.
After the reaction of linalool, thiourea and hydrobromic acid, geranyl thiourea sulfonate was obtained by p-toluenesulfonic acid treatment, and then saponified by sodium hydroxide, so that the aromatic raw material thiogeraniol with the aroma of jam and grapefruit was obtained. New spices synthesized from linalool are constantly emerging.
Linalool is a tertiary alcohol. Because of its steric shielding in structure, esterification reaction is much more difficult than that of primary alcohol and secondary alcohol, and dehydration, cyclization, isomerization and other reactions are easy to occur. In the esterification process of acetic acid, linalyl acetate cannot be prepared under the action of inorganic acids. It can only be prepared by the reaction of linalool and acetic anhydride at low temperature, using a special complex of phosphoric acid and acetic anhydride as a catalyst.
Nerol and geraniol can be obtained simultaneously when linalool is synthesized from β-pinene.
In addition, methyl heptenone, an intermediate of linalool, can be further synthesized into terpenoids such as geraniol and nerol. At PH=3, linalyl acetate can also obtain three acyclic alcohols-linalool, nerol, geraniol and a small amount of cyclic alcohol-α-terpineol.
In the presence of catalyst, linalool will be isomerized into geraniol and various terpineols. Similarly, geraniol can be isomerized to linalool under the action of SiO _ 2-Al _ 2O _ 3-FeSO _ 4 ternary catalyst.
The molecular formula of linalool is C 10H 18O. It belongs to terpenoid alcohol, which has two isomers, α-and β-,as well as levorotatory and dextrorotatory isomers. Most essential oils from different sources are a mixture of isomers. Racemate exists in perilla, jasmine or synthetic linalool oil. Specific gravity 0.865( 15℃), boiling point 195-200℃, specific curl+19.30; Levosome exists in camphor oil, safrole oil, lemon oil, lavender oil, rosewood oil (the total alcohol content is more than 82% in linalool) and other essential oils. The specific gravity is 0.8622, the boiling point is 198℃, and the specific rotation is -20. 10. Linalool is a colorless liquid. It has the fragrance of lily of the valley, but it is different from the source. Almost insoluble in water, insoluble in glycerol. Soluble in propylene glycol, nonvolatile oil and mineral oil, miscible in ethanol and ether. Refractive index: 1.4600 ~ 1.4640.
It has a strong green and sweet woody smell, just like rosewood. There are floral scents of lilacs, lilies of the valley and roses, as well as wood and fruit. The fragrance is soft, light, penetrating and not long-lasting. The green calyx and green stem of plants often contain this fragrance. Left-handed is sweet, right-handed is clear, and its fragrance is mainly used, so right-handed fragrance is better. The aroma of Cinnamomum camphora from different sources is very different. Natural linalool has a fragrance, but it is often not a single fragrance. The aroma of synthetic linalool is generally pure and harmonious.
Essential oils such as aromatic oil, camphor oil, rosewood oil and Galois oil can be used as raw materials, which can be obtained by fractionation or synthesized by chemical methods. At present, there are two main routes to synthesize linalool from turpentine:
1 and β -pinene were pyrolyzed at high temperature to produce myrcene, and then linalool was prepared by hydrochloric acid, esterification and saponification. Other alcohols produced by this method include nerol, geraniol, lauryl alcohol and terpineol. The method has high yield.
2. α -pinene is hydrogenated to pinane, then oxidized to pinane hydroperoxide, then reduced to pinane alcohol, and finally pyrolyzed to obtain linalool.
Main source: There are three ways:
1. It comes from various natural essential oils rich in linalool, such as linalool oil, linalool leaf oil, Galois oil, rosewood oil, magnolia oil, coriander oil, etc. Obtained by rectification and single separation;
The second is semi-synthetic;
Third, they are all synthetic.
Many species of Lauraceae trees contain linalool, but the content of linalool in essential oil is different due to hybridization during planting. Linalool is the main component in the essential oil of wild evergreen tree rose produced in the Amazon river basin (the total alcohol content is as high as 82% in linalool), and other components are terpenes, dipentene, eugenol, nerol and so on. ) is an excellent raw material for extracting linalool. The former Soviet Union planted a lot of coriander to extract its essential oil, and then separated it.
(1) on mosquitoes and flies;
Liquid medicine containing 2% linalyl acetate ozonide and 98% mineral oil was applied to the skin to repel mosquitoes and flies. Can be used as repellent for cockroaches, ants, lice, etc. It can also be used in textile materials to drive away pests.
It is also found that foods containing linalool can significantly reduce the foraging and oviposition of houseflies, because maggots can only develop on organisms rich in microorganisms, so pregnant females will detect and avoid laying eggs on linalool substances with strong antibacterial effect.
(2) Acaricide:
Linalool has acaricidal ability, which is effective for both larvae and adults. It is reported that the anti-mite activity test was carried out on a stored food mite. It is also reported that the formula composed of more than 20 kinds of volatile oil components such as linalool has satisfactory effects on dust mites and edible tyrophagus.
(1) Improve fat quality:
It is reported in Japan that the oil containing a small amount of linalool and linalyl acetate can be heated at 100℃ for a long time, and its smell is better than that of the control group. If some derivatives of linalool are used in combination with vitamin E, it has obvious synergistic antioxidant effect on lard, palm oil and other oils.
(2) stable foam energy:
Adding a small amount of linalool to the spray-type water-based cleaning agent containing nonionic or anionic surfactants can effectively increase the stability of foam.
(3) Tea-based aromatic beverages:
According to data analysis, the relative content of linalool in the aroma components of tea (green tea) is 19.88%, which is one of the most important aroma components. According to the patent introduction, 250g tea was extracted with water, diluted to 10L, and a small amount of spices such as methyl anisate and linalool were added. After evaluation, the fragrance of tea leaves is stronger than that of untreated tea.
(4) mildew inhibitor:
Linalool and its acetate can inhibit the growth of fungal spores or mycelium, and can be used as fungicides for fungal infections or other antifungal materials.
(5) Animal repellent:
The essence made of linalool, geraniol and phenylethanol has a good repellent effect on birds such as sparrows, crows and pigeons.
(6) Bad odor masking agent for daily chemical products:
Adding 1-5% linalool and its esters to kerosene can be used as a deodorant for burning kerosene.
Adding 0.0 1-2% linalool to detergent containing protease can mask the bad smell of enzyme preparation. Similarly, when used in bleaching agents containing enzymes, bleached textiles can have good fragrance.
Adding terpenoid essential oils such as linalool to textile softener can also achieve the purpose of covering up odor.
Adding 1% linalool or linalool essential oil to the liquid medicine of permanent curling agent can remove the bad smell left on hair by curling agent.
I hope it will help you, and I wish you good health and all the best! Hope to adopt thank you! ! !