89-83-8 Usage
Chemical Properties
Different sources of media describe the Chemical Properties of 89-83-8 differently. You can refer to the following data:
1. white crystals or powder with a pungent odour
2. Thymol occurs as colorless or often large translucent crystals, or as
a white crystalline powder with a herbal odor (aromatic and thymelike)
and a pungent caustic taste.
3. Thymol is the main constituent
of thyme and some origanum oils; it also occurs in many other essential
oils. It forms colorless crystals (mp 51.5°C) with a spicy, herbal, slightly medicinal
odor reminiscent of thyme. Thymol is prepared on a technical scale in a continuous
high-temperature, high-pressure, liquid-phase, ortho-alkylation process,
fromm-cresol and propylene, in the presence of activated aluminumoxide hydrate.The crude thymol mixture, consisting of approximately 60% thymol, unreacted
m-cresol (about 25%), and other (iso)propyl-substituted products, is separated by
fractional distillation. Most of the by-products are recycled.
Thymol is used as a dry top note in lavender compositions, in men’s fragrances,
and as a disinfectant in oral care products. It is also important as a startingmaterial
for the production of racemic menthol.Anethole is used in large quantities in the alcoholic beverage industry and
in oral hygiene products. Some crude anethole is converted into anisaldehyde.
4. Thymol has a characteristic herbaceous, warm and aromatic odor with a sweet, medicinal, spicy flavor
Occurrence
Reported in the essential oils of Monarda punctata, Satureia thymera, Origanum floribundum, Ocimum viride,
Ocimum gratissimum and particularly in thyme (Thymus vulgaris L., T. capitatus, T. serpillum L.), where it is contained up to 50%.
Also reported found in citrus peel oils, orange and tangerine juice, bilberry, cranberry, blueberry, papaya, blackberry, celery seed,
chive, clove bud, cumin seed, ginger, peppermint oil, corn mint oil, Scotch spearmint oil, nutmeg, parsley, thyme, Gruyere cheese,
parmesan cheese, romano cheese, white wine, black tea, plum, sweet and wild marjoram, fenugreek, mango, cardamom, dill herb
and seed, licorice, lovage leaf, buckwheat, sweet corn, elder flower, cherimoya, rosemary, lemon balm, Spanish sage, anise hyssop,
sweet grass oil, eucalyptus oil and mastic gum oil.
Uses
Different sources of media describe the Uses of 89-83-8 differently. You can refer to the following data:
1. Thymol is used as a preservative in halothane. It acts as an anesthetic, antiseptic in mouth wash, stabilizer in pharmaceutical preparations. It inhibits the growth and lactate production as well as reduces the uptake of cellular glucose within the bacteria. It is an active ingredient in toothpastes like euthymol. It is involved to control varroa mites and prevent fermentation and the growth of mold in bee colonies.
2. Thymol is an antimicrobial compound which can increase the efficacy of antibiotics involving drug resistant bacteria. It inhibits growth and lactate production as well as reduces cellular glucose upta
ke within the bacteria.
Production Methods
Thymol is obtained from the volatile oil of thyme (Thymus vulgaris
Linne′ (Fam. Labiatae)) by fractional distillation followed by
extraction and recrystallization. Thyme oil yields about 20–30%
thymol. Thymol may also be produced synthetically from pcymene,
menthone, or piperitone, or by the interaction of m-cresol
with isopropyl chloride.
Definition
thymol: A pungent-smelling colourless crystalline compound, C10H14O;m.p. 51°C. It occurs in various essentialoils, particularly oil of thyme,and can be made by using iron(III)chloride to oxidize piperitone (itselfextracted from eucalyptus oil). Itsantiseptic properties are exploited ingargles and mouthwashes.
Aroma threshold values
Detection: 86 to 790 ppb
Taste threshold values
Phenolic, medicinal, woody and spicy
General Description
Thymol is a monoterpene phenol derivative. It is a key volatile aroma constituent of the essential oil of plants such as thyme, basil, and oregano. It has strong antioxidant, antibacterial, anticarcinogenesis, anti-inflammatory, and antiseptic properties.
Flammability and Explosibility
Notclassified
Pharmaceutical Applications
Thymol is a phenolic antiseptic, which has antibacterial and
antifungal activity. However, it is not suitable for use as a
preservative in pharmaceutical formulations because of its low
aqueous solubility. The antimicrobial activity of thymol against
eight oral bacteria has been studied in vitro. Inhibitory activity was
noted against almost all organisms, and a synergistic effect was
observed for combinations of thymol and eugenol, and of thymol
and carvacrol. The activity of thymol against bacteria commonly
involved in upper respiratory tract infections has also been
shown.
Thymol is a more powerful disinfectant than phenol, but its low
water solubility, its irritancy to tissues, and its inactivation by
organic material, such as proteins, limit its use as a disinfectant.
Thymol is chiefly used as a deodorant in antiseptic mouthwashes,
gargles, and toothpastes, such as in Compound Thymol Glycerin
BP, in which it has no antiseptic action.
Thymol is also a true antioxidant and has been used at
concentrations of 0.01% as an antioxidant for halothane,
trichloroethylene, and tetrachloroethylene. The antioxidant activity
of thymol and thymol analogues has been described.
More recently, thymol has been shown to enhance the in vitro
percutaneous absorption of a number of drugs, including 5-
fluorouracil, piroxicam, propranolol, naproxen, and
tamoxifen. Studies have also demonstrated that the melting point
of lidocaine is significantly lowered when it is mixed with
thymol.
The inhalation of thymol, in combination with other volatile
substances, is used to alleviate the symptoms of colds, coughs, and
associated respiratory disorders. Externally, thymol has been used
in dusting powders for the treatment of fungal skin infections;
thymol has been shown to have synergistic antifungal effects when
combined with ketoconazole. Thymol was formerly used in the treatment of hookworm infections but has now been superseded by
less toxic substances.
In dentistry, thymol has been mixed with phenol and camphor to
prepare cavities before filling, and mixed with zinc oxide to form a
protective cap for dentine.
Thymol has been included in food, perfume, and cosmetic
products, and has also been used as a pesticide and fungicide.
Biochem/physiol Actions
Taste at 5 ppm
Clinical Use
Isopropyl m-cresol is extracted from oil of Thymus vulgaris(thyme, of the mint family) by partitioning into alkalineaqueous medium followed by acidification. The crystals obtainedfrom the mother liquor are large and colorless, with athymelike odor. Thymol is only slightly soluble in water,but it is extremely soluble in alcohols and other organic solvents.Thymol has mild fungicidal properties and is used inalcohol solutions and in dusting powders for the treatmentof tinea (ringworm) infections.
Safety Profile
Poison by ingestion and
intravenous routes. Moderately toxic by
subcutaneous route. Experimental
reproductive effects. Mutation data
reported. An allergen. Incompatible with
acetanilide. When heated to decomposition
it emits acrid smoke and irritating fumes. An
FDA over-the-counter drug used as an
antibacterial and antifungal agent.
Safety
Thymol is used in cosmetics, foods, and pharmaceutical applications
as an excipient. However, thymol may be irritating when
inhaled or following contact with the skin or eyes. It may also cause
abdominal pain and vomiting, and sometimes stimulation followed
by depression of the central nervous system following oral
consumption; fats and alcohol increase absorption and aggravate
symptoms.
Respiratory arrest, attributed to acute nasal congestion and
edema, has been reported in a 3-week-old patient due to the
erroneous intranasal application of Karvol, a combination product
that includes thymol. The patient recovered, but it was recommended
that inhalation decongestants should not be used in
children under the age of 5 years.
LD50 (guinea pig, oral): 0.88 g/kg
LD50 (mouse, IP): 0.11 g/kg
LD50 (mouse, IV): 0.1 g/kg
LD50 (mouse, oral): 0.64 g/kg
LD50 (mouse, SC): 0.243 g/kg
LD50 (rat, oral): 0.98 g/kg
storage
Thymol should be stored in well-closed, light-resistant containers,
in a cool, dry, place. Thymol is affected by light.
Incompatibilities
Thymol is incompatible with iodine, alkalis, and oxidizing agents. It
liquefies, or forms soft masses, on trituration with acetanilide,
antipyrine, camphor, monobromated camphor, chloral hydrate,
menthol, phenol, or quinine sulfate. The antimicrobial activity of
thymol is reduced in the presence of proteins.
Regulatory Status
GRAS listed. Included in the FDA Inactive Ingredients Database
(inhalation, liquid; oral, powder for solution). Included in
nonparenteral medicines (topical creams and ointments) licensed
in the UK. Included in the Canadian List of Acceptable Nonmedicinal
Ingredients.
Check Digit Verification of cas no
The CAS Registry Mumber 89-83-8 includes 5 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 2 digits, 8 and 9 respectively; the second part has 2 digits, 8 and 3 respectively.
Calculate Digit Verification of CAS Registry Number 89-83:
(4*8)+(3*9)+(2*8)+(1*3)=78
78 % 10 = 8
So 89-83-8 is a valid CAS Registry Number.
89-83-8Relevant academic research and scientific papers
BIOACTIVE PHENOLATE IONIC COMPLEXES
-
Page/Page column 73-74, (2021/10/30)
The invention provides an isolated material, or a phenolate form of at least one phenol- containing active material, wherein the isolated material comprises one or more phenolate species and a counter ion (a cation) in the form of a metal salt, a phosphonium or an ammonium.
Preparation method of thymol
-
Paragraph 0026-0037, (2020/08/22)
The invention relates to a preparation method of thymol, and belongs to the technical field of medicine synthesis. The preparation method comprises the steps: carrying out coupling promotion on m-cresol and isopropyl chloride by adding a reaction auxiliary agent concentrated sulfuric acid and an ionic liquid, sealing a tube, carrying out a reaction at the temperature of 120-130 DEG C for 2 h, carrying out a reaction, cooling, dissolving the product in n-heptane, washing with water, concentrating and crystallizing to obtain the target product. The byproduct obtained by the method is easy to separate from the product, the production cost of the product is reduced, an expensive catalyst is not needed, the reaction time is short, the method is environment-friendly, the conversion rate of the target product is effectively improved, the purification is easy, the purity of the obtained product is high, and the method can be applied to reference substance research.
Thermal Behavior Analysis of Two Synthesized Flavor Precursors of N-alkylpyrrole Derivatives
Ai, Lvye,Liu, Mengzhen,Ji, Xiaoming,Lai, Miao,Zhao, Mingqin,Ren, Tianbao
, p. 2389 - 2397 (2019/08/01)
To expand the library of pyrrole-containing flavor precursors, two new flavor precursors—methyl N-benzyl-2-methyl-5-formylpyrrole-3-carboxylate (NBMF) and methyl N-butyl-2-methyl-5-formylpyrrole-3-carboxylate (NUMF)—were synthesized by cyclization, oxidation, and alkylation reactions. Thermogravimetry (TG), differential scanning calorimeter, and pyrolysis–gas chromatography/mass spectrometry were utilized to analyze the thermal degradation behavior and thermal degradation products of NBMF and NUMF. The TG-DTG curve indicated that the maximum mass loss rates of NBMF and NUMF appear at 310 and 268°C, respectively. The largest peaks of NBMF and NUMF showed by the differential scanning calorimeter curve were 315 and 274°C, respectively. Pyrolysis–gas chromatography/mass spectrometry detected small molecule fragrance compounds appeared during thermal degradation, such as 2-methylpyrrole, 1-methylpyrrole-2-carboxylic acid methyl ester, limonene, and methyl formate. Finally, the thermal degradation mechanism of NBMF and NUMF was discussed, which provided a theoretical basis for their application in tobacco flavoring additives.
METHOD FOR PRODUCING ALKYLPHENOLS
-
Paragraph 0053-0057; 0060-0064, (2019/12/05)
PROBLEM TO BE SOLVED: To provide an economically excellent and industrially advantageous method for producing 6-tert-butyl-4-isopropyl-3-methylphenol and 4-isopropyl-3-methylphenol. SOLUTION: The method for producing 6-tert-butyl-4-isopropyl-3-methylphenol by isopropylation of 6-tert-butyl-3-methylphenol is characterized by using an isopropylating agent in an amount of 1.0 mol equivalent or more based on 6-tert-butyl-3-methylphenol. The method for producing 4-isopropyl-3-methylphenol comprises subjecting 6-tert-butyl-4-isopropyl-3-methylphenol produced by the above-mentioned production method to debutylation. SELECTED DRAWING: None COPYRIGHT: (C)2019,JPOandINPIT
Alkylation of Phenols with tert-Butanol Catalyzed by H-Form of Y Zeolites with a Hierarchical Porous Structure
Bayguzina,Makhiyanova,Khazipova,Khusnutdinov
, p. 1554 - 1559 (2019/10/14)
tert-Butyl-substituted phenols have been synthesized via the reaction of phenol, o-, m-, and p-cresols with tert-butanol under the action of CBr4-promoted Y-zeolites in the H-form with a hierarchical porous structure.
Heterogeneously Catalysed Oxidative Dehydrogenation of Menthol in a Fixed-Bed Reactor in the Gas Phase
Kulik, Anna,Neubauer, Katja,Eckelt, Reinhard,Bartling, Stephan,Panten, Johannes,K?ckritz, Angela
, p. 1066 - 1075 (2019/06/24)
For the first time, the oxidative dehydrogenation of (?)-menthol to (?)-menthone and (+)-isomenthone in a marketable quality was carried out in a continuous gas phase reactor as a sustainable process using molecular oxygen as green oxidant and solid catalysts which do not contaminate the product mixture and which are easily to remove. The diastereomeric purity remained largely unchanged. Three types of catalysts were found to be very active and selective in the formation of menthone and isomenthone: AgSr/SiO2, CuO distributed on a basic support and RuMnCe/CeO2, where Ru, Mn and Ce exist in an oxidized state. The best overall yield of menthon/isomenthone obtained with an Ag-based catalyst was 58 % at 64 % selectivity, with a Cu-based catalyst 41 % at 51 % selectivity and with a Ru-based catalyst 68 % at 73 % selectivity. Reaction conditions were widely optimized.
Method for preparing menthone
-
Paragraph 0072-0073; 0076-0081, (2019/02/13)
The invention discloses a method for preparing menthone. In the method, menthone is synthesized by reaction of isopulegol with a catalytic active component loaded on modified resin as a catalyst. Thecatalytic active component is loaded on the resin by low temperature ultraviolet treatment, and isopulegol is made into menthone by heterogeneous catalysis under mild conditions. The catalytic activecomponent is loaded on the resin; because of the synergistic action of the catalytic active component and the resin, the reaction can be carried out efficiently and rapidly under the mild conditions,the conversion rate of the reaction can reach 90-99.9%, the chemical selectivity can reach 89-99.9%, the catalyst has a long life, the activity of the catalyst is basically stable after the catalyst is reused for 20 times, and the catalyst is reused maximally for 50 times.
Thymol, and preparation method and pharmaceutical composition thereof
-
Paragraph 0059-0062; 0067-0070; 0072; 0075-0078; 0083-0086, (2019/01/07)
The invention discloses thymol, and a preparation method and pharmaceutical composition thereof. The preparation method comprises the steps of: conducting a condensation reaction on m-cresol and ethylacetoacetate to obtain 4,7-dimethylcoumarin, performing hydrolysis decarboxylation on the 4,7-dimethylcoumarin under conditions of a strong alkali and high temperature to obtain an organic phase C containing 5-methyl-2-(prop-1-en-2-yl)phenol, and reducing the organic phase C to obtain thymol. The preparation method of thymol disclosed by the invention is mild in conditions, does not need specialreaction equipment, and facilitates industrial production. With the preparation method, position selectivity is high, almost no position isomer is generated, the separated product is high in purity, the total yield is high and the product quality accords with current drug declaration requirements.
Selective alkylation of m-cresol with isopropyl alcohol under solvent-free conditions
Teodorescu, Florina,Enache, Adrian,Sandulescu, Madalina
, p. 58 - 66 (2017/07/26)
The outcome of the solvent free alkylation of m-cresol with isopropyl alcohol over strong acid resin catalyst has been investigated under microwave irradiation as well as conventional heating. The various reaction parameters like catalyst amount, mole rat
Thyme camphor synthesis process
-
Paragraph 0023-0031, (2017/03/18)
The invention discloses a thyme camphor synthesis process which comprises the following steps: alkylation: a G-type solid acid is taken as a catalyst, liquid m-cresol is pumped with a pump into a preheating section of a synthesis reactor, the flow rate is controlled with a flowmeter and an adjusting valve, propylene gas enters the preheating section of the synthesis reactor after being measured by the flowmeter, m-cresol and propene gas are preheated, the preheated mixture enters a reaction section of the synthesis reactor, the generated thyme camphor mixed solution is discharged after being cooled to 40 to 70 DEG C, and unreacted propene gas enters the synthesis reactor again after being compassed by a compressor for reaction, wherein the molar ratio of m-cresol to propene is 1:(1 to 5), the preheating temperature is 180 to 190 DEG C, the reaction temperature is 200 to 250 DEG C, and the reaction pressure is 0.1 to 0.3 MPa; rectification; solvent crystallization. The fixed bed catalyst, namely the G-type solid acid, is excellent in stability; the highest conversion rate of m-cresol is 82.1 percent; the highest product selectivity is 92.9 percent; the thyme camphor yield reaches up to 76.3 percent; recycling is realized; the reaction utilization ratio is high; the synthesis reaction is controlled automatically; the production is continuous; the technology is simple; the reaction cost is low.
