499-75-2

Basic information

• Product Name: Carvacrol
• Synonyms: 1-Hydroxy-2-methyl-5-isopropylbenzene;2-Hydroxy-1-methyl-4-(1-methylethyl)benzene;2-hydroxy-4-(2-propyl)toluene;2-hydroxy-p-cymen;2-methyl-5-(1-methylethyl)-pheno;2-para-cymenol;2-p-Cymenol;3-isopropyl-6-methyl-pheno
• CAS NO: 499-75-2
• Molecular Formula: C₁₀H₁₄O
• Molecular Weight: 150.22
• EINECS: 207-889-6
• Product Categories: Alcohols and Derivatives;Miscellaneous Natural Products
• Mol File: 499-75-2.mol

Chemical Properties

• Melting Point: 3-4 °C(lit.)
• Boiling Point: 236-237 °C(lit.)
• Flash Point: 224 °F
• Appearance: liquid
• Density: 0.976 g/mL at 20 °C(lit.)
• Vapor Pressure: 3.09-6.664Pa at 25℃
• Refractive Index: n20/D 1.522(lit.)
• Storage Temp.: ?20°C
• Solubility: 1.25g/l
• PKA: 10.38±0.10(Predicted)
• Water Solubility: Insoluble
• Stability: Stable. Combustible. Incompatible with strong bases, strong oxidizing agents.
• Merck: 14,1872
• BRN: 1860514
• CAS DataBase Reference: Carvacrol(CAS DataBase Reference)
• NIST Chemistry Reference: Carvacrol(499-75-2)
• EPA Substance Registry System: Carvacrol(499-75-2)

Safety Data

• Hazard Codes: C
• Statements: 22-34
• Safety Statements: 26-36/37/39-45
• RIDADR: UN 3265 8/PG 3
• WGK Germany: 3
• RTECS: FI1225000
• HazardClass: 8
• PackingGroup: III
• Hazardous Substances Data: 499-75-2(Hazardous Substances Data)

Usage

Artificial flavor

Carvacrol is the isomeric body of thymol with similar aroma as thymol. Carvacrol naturally exists in thyme oil and other essential oils, having especially high content in the thyme oil produced in Spain. Carvacrol is mainly used in the preparation of dill, girofle, mint and vanilla flavor to be used for toothpaste, toothpaste powder, oral products, talcum powder, soap and daily industrial products. In medicine, it is used for local anesthetics. In addition, carvacrol is capable of killing bacteria and intestinal parasites and can be used as disinfectants and fungicides. According to the information reported, the acute toxicity data of carvacrol: oral LD50810mg/kg (rat), skin test: LD50> 5g/kg (rabbit). Thyme plant has its origin including the Northeast, Hebei, and Inner Mongolia, Gansu, Qinghai and Xinjiang and other provinces. Ingredients: whole plant of thyme contains about 0.15~0.5% volatile oil (in oil, the component mainly contains carvacrol, paraffin, thymol), amaroid and tannin. Leaves contain free oleanolic acid, ursolic acid, caffeic acid and so on. Thyme can be not only used in medicine, for spices, but also be as the superior natural health ingredients of the processed foods. Since the 1980s, thyme-like herbal foods have become very popular. Studies have shown that thyme-containing volatile oils, in addition to being used as seasoning and for treatment of illnesses, also have anti-corrosion, antibacterial and other functions. Therefore, the consumers can benefit a lot using it as food raw materials. Because of this, in Europe, natural herbal tea also contains thyme. For example, a kind of herb tea raw material having anti-cough effect and being able to prevent and treat bronchitis has 10% thyme leaves. Image 1: Thymus plant

Chemical properties

Different sources of media describe the Chemical properties of 499-75-2 differently. You can refer to the following data:
1. Use sulfuric acid to sulfonate the p-isopropyl toluene, generating p-isopropyl toluene-2-sulfonic acid. Then we can obtain carvacrol after alkali melting treatment. Image 2: Preparation of carvacrol from p-isopropyltoluene Carvacrol, when co-melted together with potassium hydroxide, can give 2-hydroxy-4-isopropyl benzoic acid while reaction with phosphorus pentachloride can generate 2-chloro-1-methyl-4-isopropyl benzene. In acetic acid, it reaction with 1 mol Bromine can generate 4-bromocarbinol while its reaction with 2 mol bromine can generate 4, 6-dibromo carvacrol; if reacted with bromine and aluminum, we can obtain tetrabromo-o-cresol. It is easily soluble in concentrated sulfuric acid to produce 2-methyl-5-isopropyl phenol-4-sulfonic acid. In aqueous sodium hydroxide solution, it can be reacted with formaldehyde to generate carvacrol phenols alcohol: Image 3: The reaction between carvacrol and formaldehyde for generation of carvacrol phenolic alcohol It exhibits green color when reacted with ferric chloride in ethanol with no significant color in the water.
2. It appears as colorless to pale yellow slightly viscous oil. When placed in air and light, its color becomes darker. It has spicy, cool incense, herbs incense with thymol-like smell. It has a boiling point of 238 ° C, the melting point of 0.5 to 1 ° C and the flash point of 100 ° C. It is soluble ethanol, ethyl ether, propylene glycol and alkali, do not dissolve in water. It is miscible in oil. The natural products are found in thyme oil (about 70%), oregano oil (about 80%) and mange to oil and so on.

Content analysis

It can be determined by the non-polar column method by GT-10-4.

Toxicity

GRAS (FEMA). LD50: 810 mg/kg (rat, oral).

Usage limit

FEMA (mg/kg): soft drinks 26; cold drinks 34; candy 92; baked goods 120; condiments 37. Take appropriate as limit (FDA § 172.515, 2000). Allow to use (GB 2760-1996).

Standard for Maximum Allowable Amount

▼▲ Name of additive Field allowed to use it as additive Function of additive Maximal allowable amount（g/kg） arvacrol Food Food spices The perfume ingredients used in formulating fragrances shall not exceed the maximum allowable documented amount in GB 2760

Application

Spices; It is mainly used for the preparation of dill, girofle, meat, peppermint, vanilla flavor and so on. It can be used for the preparation of spices, fungicides and disinfectants. As a spice, it can be used in toothpaste, soap and other daily necessities, but also for food flavors. It can be used for spices, food additives, feed additives, antioxidants, sanitation fungicide, insect repellent, preservatives, deodorant and pharmaceutical intermediates.

Preparation

Different sources of media describe the Preparation of 499-75-2 differently. You can refer to the following data:
1. It can be obtained through treatment of the essential oil containing rich content of natural carvacrol followed by ether extraction or steam distillation to derive it. It can be derived by the sulfonation of thymol followed by alkali treatment.
2. From p-cymene by sulfonation and subsequent alkali fusion.

Category

Pesticides

Toxic classification

middle-level poisoning

Acute toxicity

Oral-rat LD50: 810 mg/kg; intravenous-mouse LD50: 80 mg/kg Stimulation Data Skin-Rabbit 500 mg/24 h Severe

Flammability and Hazardous characteristics

It is flammable upon heat, fire and strong oxidants with thermal decomposition releasing spicy stimulated smoke

Storage and transportation characteristics

Treasury: low temperature, ventilated and dry; avoid fire and high temperature; store it separately from oxidant.

Extinguishing agent

fog, carbon dioxide, foam, dry powder

Chemical Properties

Different sources of media describe the Chemical Properties of 499-75-2 differently. You can refer to the following data:
1. liquid
2. Carvacrol has a characteristic pungent, warm odor. The commercial product consists of a mixture of isomers differing because of the position of the isopropyl radical. The odor characteristics differ between the technical (lower grade) and pure (higher grade) commercial products.

Occurrence

Reported found in cumin seed, thyme, oregano, calamus, lovage, myrtle and lemon balm.

Uses

Different sources of media describe the Uses of 499-75-2 differently. You can refer to the following data:
1. Reference Standard in the analysis of herbal medicinal products
2. Carvacrol is a flavoring agent that is a colorless to pale yellow liquid. it has a spicy and pungent odor, resembling thymol. it is insoluble in water and soluble in alcohol and ether. it is a mixture of the isomeric carvacrols (isopropyl o-creols), and is obtained by chemical synthesis. it is also an ingredient of savory, a fragrant herb in nature.
3. As disinfectant; in organic syntheses.

Definition

ChEBI: A phenol that is a natural monoterpene derivative of cymene. An inhibitor of bacterial growth, it is used as a food additive. Potent activator of the human ion channels transient receptor potential V3 (TRPV3) and A1 (TRPA1).

Aroma threshold values

Detection at 2.29 ppm.

Taste threshold values

Taste characteristics at 5.0 ppm: spicy, herbal phenolic, medicinal and woody.

General Description

Produced and qualified by HWI pharma services GmbH.Exact content by quantitative NMR can be found on the certificate.

Flammability and Explosibility

Notclassified

Safety Profile

Poison by ingestion, intravenous, and subcutaneous routes. Moderately toxic by skin contact. A severe skin irritant. Combustible liquid. When heated to decomposition it emits acrid smoke and irritating fumes.

InChI:InChI=1/C10H14O/c1-7(2)9-5-4-8(3)10(11)6-9/h4-7,11H,1-3H3

Synthetic route

Carvone (99-49-0, 22327-39-5) → carvacrol (499-75-2)

Conditions	Yield
With montmorillonite In 5,5-dimethyl-1,3-cyclohexadiene at 20 - 160℃; Temperature; Solvent; Autoclave; Green chemistry; Industrial scale;	99%
With 5 weight% palladium(0) nanoparticles supported on mesoporous natural phosphate In neat (no solvent) for 24h; Reflux;	94%
With toluene-4-sulfonic acid In 1,4-dioxane; chlorobenzene at 180℃; under 2475.2 Torr; for 0.583333h; Irradiation;	85%

5-(1-Hydroxy-1-methyl-ethyl)-2-methyl-cyclohex-2-enone (7712-46-1) → carvacrol (499-75-2)

Conditions	Yield
With Amberlyst-15 cation exchange resin In toluene at 120 - 150℃; Temperature; Solvent; Reagent/catalyst;	98%

(S)-p-mentha-6,8-dien-2-one (2244-16-8, 6485-40-1) → carvacrol (499-75-2)

Conditions	Yield
In water at 180 - 250℃; for 0.166667h;	95%
at 160 - 180℃;

carvacryl acetate (6380-28-5) → carvacrol (499-75-2)

Conditions	Yield
silica gel; toluene-4-sulfonic acid In water; toluene at 80℃; for 18h;	94%

(+)-(1S,4S,5R,6R)-1,5,6-trihydroxy-2-menthene → carvacrol (499-75-2)

Conditions	Yield
With iodine In toluene for 5h; Reflux;	94%

(4R,6R)-carveol (99-48-9, 1197-06-4, 1197-07-5, 2102-58-1, 2102-59-2, 5157-78-8, 5503-11-7, 7632-16-8, 18383-51-2) → carvacrol (499-75-2)

Conditions	Yield
With palladium 10% on activated carbon at 135℃; for 1h; Temperature;	91%

5-Isopropenyl-2-methyl-cyclohex-2-enol (99-48-9) → carvacrol (499-75-2)

Conditions	Yield
With 5 weight% palladium(0) nanoparticles supported on mesoporous natural phosphate In neat (no solvent) for 24h; Reflux;	90%

(R)-Carvone (6485-40-1, 2244-16-8) → carvacrol (499-75-2)

Conditions	Yield
With tert-butyldimethylsilyl 2-methylpropane-2-sulfonate; platinum(IV) chloride In toluene at 80℃; for 2h; Inert atmosphere; regioselective reaction;	87%
With triethylsilyl chloride; triethylamine; sodium iodide In acetonitrile at 4℃;	67%
With chloro-trimethyl-silane; water for 3h; Ambient temperature;
In water Heating; Acidic conditions;
With aqueous acid Heating;

(R)-1-(1-Hydroxy-1-methyl-ethyl)-4-methyl-bicyclo[3.1.0]hexan-3-one (130912-76-4) → carvacrol (499-75-2) + (5S,6S)-5-Bromo-3-isopropyl-6-methyl-cyclohex-2-enone

Conditions	Yield
With hydrogen bromide In dichloromethane for 1.5h; Ambient temperature;	A 10% B 85%

(R)-Carvone (6485-40-1, 2244-16-8) → carvacrol (499-75-2) + (5R)-5-(1-chloro-1-methylethyl)-2-methylcyclohex-2-enone (85710-71-0)

Conditions	Yield
With hydrogenchloride; silica gel In water at 0 - 20℃; for 0.75h; Time;	A 11% B 83%

ortho-cresol (95-48-7) + isopropyl alcohol (67-63-0) → carvacrol (499-75-2)

Conditions	Yield
With diatomaceous earth phosphoric acid at 135℃; for 6h; Temperature;	82.3%
With phosphorus pentoxide
With aluminum (III) chloride In dichloromethane at -5℃; for 4h; Solvent; Reagent/catalyst; Large scale;	75.6 kg

2-hydroxy-5-isopropenyl-2-methylcyclohexanone → carvacrol (499-75-2)

Conditions	Yield
With phosphorus pentoxide In 1,4-dioxane at 98 - 108℃; for 2h; Solvent;	81%

(+)-(4S,5R,6S)-5,6-dihydroxy-1(7),2-menthadiene → carvacrol (499-75-2)

Conditions	Yield
With hydrogenchloride In tetrahydrofuran; water at 20℃; for 5h;	80%

(+)-Δ5-dehydro-1-hydroxyisocarvomenthol → carvacrol (499-75-2)

Conditions	Yield
With iodine In toluene for 5h; Reflux;	80%

p-menth-3-en-2-one (23733-68-8) → carvacrol (499-75-2)

Conditions	Yield
With Cu-C composite catalyst In 5,5-dimethyl-1,3-cyclohexadiene at 190 - 220℃; Solvent; Green chemistry;	78%
With copper in charcoal In 5,5-dimethyl-1,3-cyclohexadiene at 190 - 220℃; Concentration; Solvent;	77%
With copper in charcoal In 5,5-dimethyl-1,3-cyclohexadiene at 190 - 230℃; Reflux;	77%

(R)-Carvone (6485-40-1, 2244-16-8) + chloroacetonitrile (107-14-2) → carvacrol (499-75-2) + 8-(chloroacetylamino)-p-menth-6-en-2-one (128011-29-0)

Conditions	Yield
With sulfuric acid at -25 - 20℃; Ritter reaction;	A n/a B 68%

(+)-Δ5-dehydro-1-hydroxyisocarvomenthol → carvacrol (499-75-2) + carvotanacetone (499-71-8)

Conditions	Yield
With iodine In toluene for 3h; Reflux;	A 64% B 26%

formic acid 5-isopropyl-2-methyl-phenyl ester → carvacrol (499-75-2) + 2-hydroxy-6-isopropyl-3-methyl-benzaldehyde (1665-99-2)

Conditions	Yield
With boron tribromide; iron(III) chloride In chlorobenzene at -15 - 12℃; for 3h; Fries rearrangement;	A n/a B 55%

4-Chlorobutyronitrile (628-20-6) + (R)-Carvone (6485-40-1, 2244-16-8) → carvacrol (499-75-2) + 8-(4-chlorobutyramido)-6-p-menthen-2-one

Conditions	Yield
With sulfuric acid at -25 - 20℃; Ritter reaction;	A n/a B 54%

pentanonitrile (110-59-8) + (R)-Carvone (6485-40-1, 2244-16-8) → carvacrol (499-75-2) + 8-valeramido-6-p-menthen-2-one

Conditions	Yield
With sulfuric acid at -25 - 20℃; Ritter reaction;	A n/a B 53%

(R)-Carvone (6485-40-1, 2244-16-8) + benzonitrile (100-47-0) → carvacrol (499-75-2) + 8-benzoylamino-p-menth-6-en-2-one (128011-32-5)

Conditions	Yield
With sulfuric acid at -25 - 20℃; Ritter reaction;	A n/a B 48%

(R)-1-(1-Hydroxy-1-methyl-ethyl)-4-methyl-bicyclo[3.1.0]hexan-3-one (130912-76-4) → carvacrol (499-75-2) + (5S,6S)-5-Chloro-3-isopropyl-6-methyl-cyclohex-2-enone

Conditions	Yield
With hydrogenchloride In dichloromethane for 1.5h; Ambient temperature;	A 40% B 45%

acetonitrile (75-05-8) + /PRSGG643-3025/ → carvacrol (499-75-2) + 8-acetylamino-p-menth-6-en-2-one (128011-28-9) + /PRSGG643-3027/

Conditions	Yield
With sulfuric acid at 0 - 20℃;	A n/a B 44% C n/a

Isobutyronitrile (78-82-0) + /PRSGG643-3025/ → carvacrol (499-75-2) + 8-isobutyrylamino-p-menth-6-en-2-one (128011-31-4) + /PRSGG643-3027/

Conditions	Yield
With sulfuric acid at 0 - 20℃;	A n/a B 42% C n/a

benzonitrile (100-47-0) + /PRSGG643-3025/ → carvacrol (499-75-2) + 8-benzoylamino-p-menth-6-en-2-one (128011-32-5) + /PRSGG643-3027/

Conditions	Yield
With sulfuric acid In dibutyl ether at 0 - 20℃;	A n/a B 42% C n/a

(R)-Carvone (6485-40-1, 2244-16-8) + acetonitrile (75-05-8) → carvacrol (499-75-2) + 8-acetylamino-p-menth-6-en-2-one (128011-28-9)

Conditions	Yield
With sulfuric acid at -25 - 20℃; Ritter reaction;	A n/a B 38%

(R)-Carvone (6485-40-1, 2244-16-8) + propiononitrile (107-12-0) → carvacrol (499-75-2) + 8-propioamido-6-p-menthen-2-one

Conditions	Yield
With sulfuric acid at -25 - 20℃; Ritter reaction;	A n/a B 34%

chloroacetonitrile (107-14-2) + /PRSGG643-3025/ → carvacrol (499-75-2) + 8-(chloroacetylamino)-p-menth-6-en-2-one (128011-29-0) + /PRSGG643-3027/

Conditions	Yield
With sulfuric acid at 0 - 20℃;	A n/a B 33% C n/a

cis-piperitol (65733-27-9) → carvacrol (499-75-2)

Conditions	Yield
With selenium(IV) oxide; formic acid In 1,4-dioxane at 80℃; for 72h;	33%

carvacrol (499-75-2) + methyl iodide (74-88-4) → carvacrol methyl ether (6379-73-3)

Conditions	Yield
Stage #1: carvacrol With sodium hydroxide In tetrahydrofuran at 50℃; for 1h; Inert atmosphere; Stage #2: methyl iodide In tetrahydrofuran at 50℃; Inert atmosphere;	100%
Stage #1: carvacrol With sodium hydroxide In methanol at 20℃; for 0.25h; Williamson Ether Synthesis; Inert atmosphere; Alkaline conditions; Stage #2: methyl iodide In methanol at 65℃; for 1h; Reagent/catalyst; Williamson Ether Synthesis; Cooling; Inert atmosphere;	84%
With potassium carbonate In acetone at 60℃; for 2h;	81%
With methanol
With potassium carbonate In N,N-dimethyl-formamide at 20℃; for 24h;

carvacrol (499-75-2) → 2-methyl-5-isopropyl-4-chlorophenol (5665-94-1)

Conditions	Yield
With oxygen; lithium chloride; copper dichloride In acetic acid at 80℃; for 6h; regioselective reaction;	99%
With sulfuryl dichloride In dichloromethane at 0 - 20℃;	82%
With sulfuryl dichloride In tetrachloromethane at 0 - 20℃; for 0.75h;	81%

carvacrol (499-75-2) + allyl bromide (106-95-6) → 2-(allyloxy)-4-isopropyl-1-methylbenzene (29652-98-0)

Conditions	Yield
Stage #1: carvacrol With sodium hydrogencarbonate In dimethyl sulfoxide at 20℃; for 0.5h; Stage #2: allyl bromide In dimethyl sulfoxide at 20℃; for 8h;	98%
With water; sodium hydroxide In acetone Williamson Ether Synthesis; Reflux;	76%
Stage #1: carvacrol With potassium carbonate In N,N-dimethyl-formamide at 20℃; for 0.5h; Inert atmosphere; Stage #2: allyl bromide In N,N-dimethyl-formamide Inert atmosphere;	70%
With potassium carbonate; acetone

carvacrol (499-75-2) + 2-(bromomethyl)naphthalene (3163-27-7) → 1-((5-isopropyl-2-methylphenoxy)methyl)naphthalene

Conditions	Yield
Stage #1: carvacrol With potassium carbonate In N,N-dimethyl-formamide at 20℃; for 0.5h; Inert atmosphere; Stage #2: 2-(bromomethyl)naphthalene In N,N-dimethyl-formamide Inert atmosphere;	98%

carvacrol (499-75-2) + 2-(4-chlorophenyl) malononitrile (32122-64-8) → 2-(4-chlorophenyl)-2-(4-hydroxy-2-isopropyl-5-methylphenyl)malononitrile

Conditions	Yield
With dipotassium peroxodisulfate; copper(II) bis(trifluoromethanesulfonate) In acetonitrile at 60℃; for 18h; Inert atmosphere; Sealed tube;	98%

chloro-trimethyl-silane (75-77-4) + carvacrol (499-75-2) → 5-isopropyl-2-methylphenoxytrimethylsilane (66760-13-2)

Conditions	Yield
With triethylamine In benzene	97%

Methyltrichlorosilane (75-79-6) + carvacrol (499-75-2) → C31H42O3Si (66760-15-4)

Conditions	Yield
With triethylamine In benzene	97%

trifluoromethylsulfonic anhydride (358-23-6) + carvacrol (499-75-2) → 5-isopropyl-2-methylphenyl trifluoromethanesulfonate (63028-16-0)

Conditions	Yield
With triethylamine In dichloromethane at 0 - 23℃; for 3h;	97%
With pyridine In dichloromethane at 0 - 20℃; for 1h; Inert atmosphere;

carvacrol (499-75-2) + 4-Fluorobenzenesulfonyl chloride (349-88-2) → 2-methyl-5-isopropylphenyl 4-fluorobenzenesulfonate

Conditions	Yield
With triethylamine In dichloromethane at 20℃;	97%

carvacrol (499-75-2) + 3-nitrobenzenesulphonyl chloride (121-51-7) → 2-methyl-5-isopropylphenyl 3-nitrobenzenesulfonate

Conditions	Yield
With triethylamine In dichloromethane at 20℃;	97%

carvacrol (499-75-2) + benzoyl chloride (98-88-4) → 5-isopropyl-2-methylphenyl benzoate (100752-52-1)

Conditions	Yield
Stage #1: carvacrol With sodium hydroxide; Amberlyst A26 Stage #2: benzoyl chloride In acetone at 20℃; for 0.25h; Further stages.;	96%
With aluminum oxide; sodium hydroxide microwave irradiation;	90%
With triethylamine In dichloromethane at 0 - 20℃; for 11h; Inert atmosphere;	82%
im Druckrohr;
With picoline In dichloromethane for 1h; Reflux;

carvacrol (499-75-2) + 2-Nitrobenzenesulfonyl chloride (1694-92-4) → 2-methyl-5-isopropylphenyl 2-nitrobenzenesulfonate

Conditions	Yield
With triethylamine In dichloromethane at 20℃;	96%

carvacrol (499-75-2) → 2-methyl-5-isopropyl-4-bromophenol (121665-99-4)

Conditions	Yield
With tetra-N-butylammonium tribromide In chloroform for 0.0333333h;	95%
With tetra-N-butylammonium tribromide In methanol; dichloromethane at 20℃; for 0.166667h;	93%
With tetra-N-butylammonium tribromide In methanol; dichloromethane at 23℃; for 0.166667h;	93%

carvacrol (499-75-2) + α-halo acetic acid → 2-(5-isopropyl-2-methylphenoxy)acetic acid (19728-20-2)

Conditions	Yield
Stage #1: carvacrol With sodium hydroxide Stage #2: α-halo acetic acid In acetone for 0.333333h; Further stages.;	95%

carvacrol (499-75-2) + 3,3-dimethyl-allyl chloride (503-60-6) → 4-isopropyl-1-methyl-2-((3-methylbut-2-en-1-yl)oxy)benzene

Conditions	Yield
Stage #1: carvacrol With potassium carbonate In acetone at 20℃; for 0.166667h; Stage #2: 3,3-dimethyl-allyl chloride In acetone at 80℃; for 4h;	95%

carvacrol (499-75-2) + 4-bromobenzenesulfonyl chloride (98-58-8) → 2-methyl-5-isopropylphenyl 4-bromobenzenesulfonate

Conditions	Yield
With triethylamine In dichloromethane at 20℃;	95%

carvacrol (499-75-2) + 1-bromomethyl-4-nitro-benzene (100-11-8) → 4-isopropyl-1-methyl-2-((4-nitrobenzyl)oxy)benzene

Conditions	Yield
Stage #1: carvacrol With potassium carbonate In N,N-dimethyl-formamide at 20℃; for 0.5h; Inert atmosphere; Stage #2: 1-bromomethyl-4-nitro-benzene In N,N-dimethyl-formamide Inert atmosphere;	95%

carvacrol (499-75-2) + propionyl chloride (79-03-8) → 3-(isopropyl)-6-methylphenyl propionate (157252-17-0)

Conditions	Yield
Stage #1: carvacrol With sodium hydroxide; Amberlyst A26 Stage #2: propionyl chloride In acetone at 20℃; for 0.166667h; Further stages.;	94%
With aluminum oxide; sodium hydroxide microwave irradiation;	91%
With triethylamine In dichloromethane at 0 - 20℃; for 11h; Inert atmosphere;	75%

carvacrol (499-75-2) + acetyl chloride (75-36-5) → carvacryl acetate (6380-28-5)

Conditions	Yield
Stage #1: carvacrol With sodium hydroxide; Amberlyst A26 Stage #2: acetyl chloride In acetone at 20℃; for 0.166667h; Further stages.;	94%
With aluminum oxide; sodium hydroxide microwave irradiation;	94%
With triethylamine In tetrahydrofuran at 0 - 20℃; for 3.26667h;	86%

2-benzofuran-1(3H)-one (87-41-2) + carvacrol (499-75-2) → 2-(5'-isopropyl-2'-methyl-phenoxymethyl)-benzoic acid

Conditions	Yield
Stage #1: carvacrol With sodium methylate In methanol salt formation; Stage #2: 2-benzofuran-1(3H)-one at 150 - 160℃; for 4h; Addition; ring cleavage;	94%

carvacrol (499-75-2) + ethyl halide → 2-ethoxy-4-isopropyl-1-methylbenzene (4732-13-2)

Conditions	Yield
Stage #1: carvacrol With sodium hydroxide; Amberlite IRA 400 Stage #2: ethyl halide In acetone for 0.583333h; Further stages.;	94%

carvacrol (499-75-2) + n-butyl halide → 2-butoxy-4-isopropyl-1-methylbenzene

Conditions	Yield
Stage #1: carvacrol With sodium hydroxide Stage #2: n-butyl halide In acetone for 0.583333h; Further stages.;	94%

carvacrol (499-75-2) + n-propyl halide → 4-isopropyl-1-methyl-2-propoxybenzene (5648-33-9)

Conditions	Yield
Stage #1: carvacrol With sodium hydroxide Stage #2: n-propyl halide In acetone for 0.5h; Further stages.;	94%

carvacrol (499-75-2) + CH3CH2-Hal → 2-ethoxy-4-isopropyl-1-methylbenzene (4732-13-2)

Conditions	Yield
With aluminum oxide; sodium hydroxide microwave irradiation;	94%

carvacrol (499-75-2) + (Z)-4-(2-bromovinyl)benzoic acid (959576-29-5) → (Z)-5-isopropyl-2-methylphenyl-4-(2-bromovinyl)benzoate (1202386-11-5)

Conditions	Yield
Stage #1: carvacrol; (Z)-4-(2-bromovinyl)benzoic acid With dmap In N,N-dimethyl-formamide; benzene for 0.166667h; Stage #2: With dicyclohexyl-carbodiimide In N,N-dimethyl-formamide; benzene at 20℃; for 24h; optical yield given as %de; stereoselective reaction;	94%

carvacrol (499-75-2) + 2-chloro-N-(3,4-dichlorophenyl)acetamide (20149-84-2) → C18H19Cl2NO2 (1228237-34-0)

Conditions	Yield
With sodium hydroxide In acetone for 0.0416667h; Microwave irradiation;	94%

Upstream product

• 63843-07-2 p-mentha-4⁽⁸⁾,6-dien-2-one oxime 
• 108-20-3 di-isopropyl ether 
• 95-48-7 ortho-cresol 
• 6485-40-1 (R)-Carvone 
• 7732-18-5 water 
• 144-62-7 oxalic acid 
• 7664-93-9 sulfuric acid 
• 31198-76-2 carvoxime 
• 619-01-2 dihydrocarveol 
• 67-64-1 acetone 
• 464-49-3 (1R,4R)-1,7,7-trimethylbicyclo[2.2.1]heptan-2-one 
• 5435-44-9 (E)-3-Ureido-but-2-enoic acid ethyl ester 
• 2244-16-8 (S)-p-mentha-6,8-dien-2-one 
• 96-71-9 5-isopropyl-2-methylbenzenesulfonic acid 

Downstream Products

• 116295-53-5 phosphoric acid-(2,4-dibromo-phenyl ester)-bis-(5-isopropyl-2-methyl-phenyl ester) 
• 101821-22-1 2-isopropyl-5-methyl-[1,4]benzoquinone-1-(4-hydroxy-phenylimine) 
• 861298-25-1 N-[2-(5-isopropyl-2-methyl-phenoxy)-ethyl]-N-methyl-aniline 
• 30003-51-1 Thiocyansaeure-(4-hydroxy-3-methyl-6-isopropyl-phenylester) 
• 66760-15-4 C₃₁H₄₂O₃Si 
• 490-06-2 3-isopropyl-6-methyl-1,2-benzenediol 
• 95475-28-8 3,10-dihydroxy-6,12-di-iso-propyl-3,10-dimethyltricyclo[6.2.2.0^2,7]dodeca-5,11-diene-4,9-dione 
• 90334-19-3 3,10-dihydroxy-3,10-di-isopropyl-6,11-dimethyltricyclo<6.2.2.0^2,7>dodeca-5,11-diene-4,9-dione 
• 98-82-8 Isopropylbenzene 
• 6379-73-3 carvacrol methyl ether 

Relevant articles and documents

A Comparison of Reaction Kinetics Observed under Microwave Irradiation and Conventional Heating

Kinetic studies were made of two reactions under microwave heating and under conventional heating.The reactions were the acid-catalyzed isomerization of carvone to carvacrol and the Diels-Alder reaction between anthracene and diethyl maleate.It was found that the rates of these reactions were the same, within experimental error, under either mode of heating at the same temperature.The activation parameters for the isomerization were measured as E(excit) = 89 +/- 3 kJ/mol, ln A = 21.5 +/- 0.8 (oil bath); and E(excit) = 83 +/- 5 kJ/mol, ln A = 19.7 +/- 1.6 (microwave).The activation parameters for the Diels-Alder reaction were E(excit) = 94 +/- 10 kJ/mol, ln A = 15.6 +/- 2.3 (oil bath); and E(excit) = 88 +/- 8 kJ/mol, ln A = 13.9 +/- 2.0 (microwave).

The chemistry of thujone. XIX. 1 Acid-promoted ring cleavage of thujone-derived cyclopropylcarbinols

Thujone-derived cyclopropylcarbinols can cleave via three distinct pathways: the exo cleavage, the endo cleavage, and the interesting cyclopropylcarbinyl rearrangement. Factors determining which pathway is adopted under specific conditions are discussed. A short sequence leading to synthesis of the sesquiterpene (+)-β-cyperone is described.

3'-KETOGLYCOSIDE COMPOUND FOR THE SLOW RELEASE OF A VOLATILE ALCOHOL

The present invention relates to a 3'-ketoglycoside compound defined by formula (I) and its use for controlled release of alcohols, in particular alcohols showing an insect repellent effect. It relates also to a process for preparing the 3'-ketoglycoside compound of formula (I). It further relates to a composition comprising a 3'- ketoglycoside compound of formula (I). It relates also to the use of a 3'-ketoglycoside compound of formula (I) for the controlled release of alcohols. It related also to a method of use of such composition.

Method for synthesizing carvacrol from 8-hydroxycarvone

The invention discloses a method for synthesizing carvacrol from 8-hydroxy carvone, which comprises the following steps: dissolving the raw material 8-hydroxy carvone and a catalyst in a solvent, heating to perform dehydration and rearrangement reaction on the 8-hydroxy carvone to generate carvacrol, performing filtering to separate the catalyst after the reaction is finished, rectifying the filtrate under reduced pressure, and recycling the solvent; and further decompressing and rectifying to obtain a carvacrol finished product. The catalyst is a strong acid or weak acid cationic resin catalyst. According to the brand-new carvacrol synthesis method provided by the invention, the existing 8-hydroxy carvone is comprehensively utilized, the application range of the 8-hydroxy carvone is expanded, and the production cost of carvacrol is reduced; the method is mild in reaction condition, easy and convenient to operate and high in reaction efficiency, the product yield can reach 98%, and themethod has good industrial application prospects.

Method for preparing carvacrol by using limonene epoxide as hydrogenation acceptor

The invention discloses a method for preparing carvacrol by using limonene epoxide as a hydrogenation acceptor, and belongs to the field of fine chemical engineering. According to the method, carvacrol is synthesized by taking carvacrol as a raw material, and limonene epoxide is added as a hydrogenation acceptor. The method has the advantages that limonene epoxide can timely consume active hydrogen generated by reaction, generation of hydrogen is avoided, the reaction is carried out under normal pressure, the safety of the reaction is improved, and forward movement of dehydrogenation reaction is promoted, so that the product yield is improved; the reaction time is short and the process is simple; and the supported palladium-carbon catalyst can be repeatedly used, so that green industrial production is realized.

Method for efficiently preparing carvacrol from o-cresol

The invention discloses a method for efficiently preparing carvacrol from o-cresol, which comprises the following steps: a, carrying out alkylation reaction by using o-cresol and isopropanol as raw materials and diatomite phosphoric acid as a catalyst; b, preparation of a diatomite phosphoric acid catalyst: firstly drying the diatomite carrier at 100 DEG C; c, adopting phosphoric acid as a dipping solution and diatomite as a solid adsorbent, and dipping for 3-48 hours; and d, after the impregnation is finished, calcining the obtained diatomite at the calcining temperature. According to the method for efficiently preparing the carvacrol from the o-cresol, the content of the carvacrol is 97-99.5%, the yield is 75-85%, and the process is low in production cost, high in conversion rate, high in yield and convenient to industrialize.

Synthesis of a pyrrolidine derivative of a carvotacetone and monoterpenes for anti-methicillin-resistant Staphylococcus aureus and anti-cryptococcal properties

Monoterpene derivatives are of great biological relevance in the pharmaceutical industry. In the present study, pyrrolidine derivative of a carvotacetone, 3-O-benzylcarvotacetone (1), and selected monoterpenes (3-hydroxy-2-isopropyl-5-methyl-p-benzoquinone (3) and cis-piperitol (5)) were prepared to provide (R)-1-(4-(benzyloxy)-5-isopropyl-2-methylcyclohexa-1,3-dien-1-yl)-pyrrolidine (2), 2-isopropyl-5-methyl-3,6-dioxocyclohexa-1,4-dien-1-yl acetate (4), cis-3-hydroxypiperitone (6) and carvacrol (7). Structure of 2 was determined based on NMR and HRMS spectral data. Compound 4 exhibited activity against fungi Cryptococcus neoformans with an IC50 value of 50 value of 14.97μg/mL against methicillin resistant Staphylococcus aureus bacteria. Previous to the current study, both compound 6 and 7 had been reported to have anti-microbial and anti-fungal activities.

Novel palladium nanoparticles supported on mesoporous natural phosphate: Catalytic ability for the preparation of aromatic hydrocarbons from natural terpenes

Various ratios of palladium nanoparticles supported on mesoporous natural phosphate (Pd@NP) were prepared using the wetness impregnation method. The prepared catalysts were characterized by IR, XRD, CV, SEM, EDX, XRF, TEM and BET analysis. The reduction and preparation of the palladium nanoparticles afford a crystallite size of 10.88 nm. The performance of the synthesized catalyst was investigated in the solvent-free dehydroaromatization of α-, β- and γ-himachalene mixture from Cedrus atlantica oil as a model substrate. In order to achieve an efficient and selective catalysis, the catalytic dehydroaromatization of various terpenes such as limonene, limonaketone, carvone, carveol and perillyl alcohol was studied. The Pd@NP catalyst performed a high catalytic activity, selectivity and recyclability in the terpenes dehydroaromatization reaction.

Demethylenation of Cyclopropanes via Photoinduced Guest-to-Host Electron Transfer in an M6L4 Cage

Unusual demethylenation reactions of cyclopropanes under UV-light irradiation were found within a cavity of a photoactive coordination cage. The reaction proceeded via a guest-to-host electron transfer owing to the highly electron-deficient nature of the cage. The reactions were highly chemoselective and enabled late-stage derivatization of a steroid molecule, which led to a totally new un-natural steroid.

Biomimetic Transformation of p-Menthene Glucosides into p-Cymenes and Carvotanacetone

A biomimetic transformation of p-menthene glucosides into aromatic monoterpenoids that alluded to mechanisms for essential oil metabolism, which lines up with the precepts of molecular economy, is described. Acid treatment of (-)-(3S,4S,6R)-3,6-dihydroxy-1-menthene 3-O-β-d-glucopyranoside (1) and (-)-(3S,4R,5R,6S)-3,5,6-trihydroxy-1-menthene 3-O-β-d-glucopyranoside (2), from Ageratina glabrata, yielded p-cymene (7) and carvacrol (9). The stable oxidized intermediates (+)-(3S,4S,6R)-3,6-dihydroxy-1-menthene (3), (+)-(1S,4S,6R)-1,6-dihydroxy-2-menthene (4), (+)-(1R,4S,6R)-1,6-dihydroxy-2-menthene (5), (+)-(4S,6R)-yabunikkeol (6), (+)-(4S)-carvotanacetone (8), (+)-(1S,4S,5R,6R)-1,5,6-trihydroxy-2-menthene (15), (+)-(1R,4S,5R,6R)-1,5,6-trihydroxy-2-menthene (16), and the new (+)-(4S,5R,6S)-1(7),2-menthadiene (17) permitted establishment of the reaction mechanisms. The reactivity of the hydroxy groups of 4 and 5, as well as those of 15 and 16, was compared by acetylation reactions and supported by DFT calculations, revealing diminished reactivity in 4 and 15 due to the cis configuration of their hydroxy groups at C-1 and C-6. In addition, p-cymene (7) was detected as one of the major constituents of the essential oil of A. glabrata, which matches well with the biomimetic study.