95-87-4

Basic information

• Product Name: 2,5-Dimethylphenol
• Synonyms: XYLENOL(2,5-);1,2,5-Xylenol;1,4-Dimethyl-2-hydroxybenzene;1-Hydroxy-2,5-dimethylbenzene;2,5-dimethyl-pheno;3,6-Dimethylphenol;3,6-Xylenol;6-Methyl-m-cresol
• CAS NO: 95-87-4
• Molecular Formula: C₈H₁₀O
• Molecular Weight: 122.16
• EINECS: 202-461-5
• Product Categories: Aromatic Phenols;INTERMEDIATESOFGEMFIBROIL;Antioxidant
• Mol File: 95-87-4.mol
• Article Data: 99

Chemical Properties

• Melting Point: 75-77 °C
• Boiling Point: 212 °C(lit.)
• Flash Point: 85 °C
• Appearance: slightly brown/Crystals
• Density: 0.971 g/mL at 25 °C(lit.)
• Vapor Pressure: 0.128mmHg at 25°C
• Refractive Index: 1.5120
• Storage Temp.: room temp
• Solubility: 3.54g/l slightly soluble
• PKA: pK1:10.22 (25°C)
• Explosive Limit: 1.4%(V)
• Water Solubility: 1 g/100 mL (60 ºC)
• Merck: 14,10082
• BRN: 1099260
• CAS DataBase Reference: 2,5-Dimethylphenol(CAS DataBase Reference)
• NIST Chemistry Reference: 2,5-Dimethylphenol(95-87-4)
• EPA Substance Registry System: 2,5-Dimethylphenol(95-87-4)

Safety Data

• Hazard Codes: T,N
• Statements: 24/25-34-51/53
• Safety Statements: 26-36/37/39-45-61
• RIDADR: UN 2261 6.1/PG 2
• WGK Germany: 3
• RTECS: ZE5775000
• TSCA: Yes
• HazardClass: 6.1
• PackingGroup: II
• Hazardous Substances Data: 95-87-4(Hazardous Substances Data)

Usage

Description

2,5-Dimethylphenol, also known as 2,5-xylenol or p-xylenol, is a chemical compound with the chemical formula (CH3)2C6H3OH. It is one of the six isomers of xylenol and is found in alcoholic beverages, coffee, and whisky. As a flavoring agent, it belongs to the family of Ortho Cresols. It has significant industrial importance, particularly for the synthesis of Mexilethine and the manufacture of antioxidants. Additionally, it serves as a monomer for the production of poly (p-phenylene oxide) engineering resins through carbon-oxygen oxidative coupling. Traditionally, 2,5-dimethylphenol is extracted from coal tar and exhibits a creosote, sweet, medicinal taste.

Uses

Used in Chemical Synthesis:
2,5-Dimethylphenol is used as a chemical intermediate for the synthesis of Mexilethine, a medication used to treat certain heart rhythm disorders.
Used in Antioxidant Production:
2,5-Dimethylphenol is used as a raw material in the production of antioxidants, which are essential in various industries to prevent oxidation and degradation of materials.
Used in Resin Manufacturing:
2,5-Dimethylphenol is used as a monomer in the manufacturing of poly (p-phenylene oxide) engineering resins through carbon-oxygen oxidative coupling, contributing to the development of high-performance plastics.
Used in Flavoring and Fragrance Industry:
2,5-Dimethylphenol is used as a flavoring agent in the food and beverage industry, particularly in alcoholic beverages, coffee, and whisky, due to its distinct taste and aroma.
Used in Perfuming Agents:
2,5-Dimethylphenol is used in the production of perfuming agents, capitalizing on its unique scent to create various fragrances for personal care and household products.
Used in Lubricating Oils, Gasoline, and Elastomers:
In isomeric mixtures, 2,5-dimethylphenol is used as an antioxidant for lubricating oils, gasoline, and elastomers, enhancing their stability and performance.
Occurrence:
2,5-Dimethylphenol is reported to be found in coffee, smoked fatty fish, processed lean fish, malt whiskey, Scotch blended whiskey, katsuobushi (dried bonito), and kumazasa (Sasa albo-marginata).
General Description:
2,5-Dimethylphenol is a colorless to off-white crystalline solid with an odor threshold concentration of 0.4 mg/L and a taste threshold concentration of 0.5 mg/L. At 10 ppm, it exhibits musty, chemical, stringent, and phenolic taste characteristics.

References

https://en.wikipedia.org/wiki/2,6-Xylenol https://en.wikipedia.org/wiki/Xylenol https://pubchem.ncbi.nlm.nih.gov/compound/2_5-dimethylphenol#section=Top

Air & Water Reactions

2,5-Dimethylphenol is hygroscopic. Insoluble in water.

Reactivity Profile

2,5-Dimethylphenol is incompatible with bases, acid chlorides, acid anhydrides and oxidizing agents. 2,5-Dimethylphenol corrodes steel, brass, copper and copper alloys.

Fire Hazard

Flash point data for 2,5-Dimethylphenol are not available. 2,5-Dimethylphenol is probably combustible.

Safety Profile

Poison by ingestion. Moderately toxic by an unspecified route. When heated to decomposition it emits acrid smoke and irritating fumes. Questionable carcinogen with experimental tumorigenic data. Used in disinfectants, solvents, pharmaceuticals, plasticizers, and wetting agents. See also other xylenol entries.

Purification Methods

Crystallise 2,5-xylenol from EtOH/ether. [Beilstein 6 IV 3164.]

Upstream product

• 105-67-9 2,4-Xylenol 
• 59648-19-0 7-methyl-2-phenyl-4H-benzo[1,3,2]dioxaborinine 
• 16819-05-9 N-<(4-Hydroxy-3,6-dimethyl-phenyl)-methyl>-dimethylamin 
• 106-42-3 para-xylene 
• 877-48-5 2,5-dimethylphenyl acetate 
• 10034-85-2 hydrogen iodide 
• 108-24-7 acetic anhydride 
• 64-19-7 acetic acid 
• 16698-35-4 5,8-dimethyltocol 
• 71-23-8 propan-1-ol 
• 35774-21-1 2,5-dimethylphenyl azide 
• 14845-35-3 2,5-dimethyl-cyclohex-2-enone 
• 7705-08-0 iron(III) chloride 
• 860696-56-6 (2-carboxy-6-hydroxy-4-methyl-phenyl)-acetic acid 

Downstream Products

• 135838-96-9 4-nitro-benzoic acid-(2,5-dimethyl-phenyl ester) 
• 120983-09-7 6-(N-morpholinylmethyl)-2,5-dimethylphenol 
• 29053-91-6 2,5-dimethyl-4-morpholin-4-ylmethyl-phenol 
• 110699-67-7 2,5-dimethylphenyl 2-bromoacetate 
• 123674-30-6 1-bromo-2-(tosyloxy)-3,6-dimethylbenzene 
• 51866-62-7 α,α,α',α'-tetrakis(2,5-dimethyl-4-hydroxyphenyl)-p-xylene 
• 15081-25-1 benzoic acid 2,5-dimethyl-phenyl ester 
• 835-84-7 2-(benzyloxy)-1,4-dimethylbenzene 
• 3169-79-7 (2,5-dimethyl-phenyl)-(2-nitro-phenyl)-ether 
• 1440-66-0 Chloressigsaeure-(2,5-dimethyl-phenylester) 
• 17959-07-8 2-Hydroxy-5-nitro-3,6-dimethyl-benzylchlorid 
• 4626-23-7 3,6-Dimethyl-2-thiomethoxymethyl-phenol 
• 3921-12-8 3,6-dimethylsalicylic acid 
• 62594-95-0 2,5-Dimethyl-6-(1-phenylethenyl)phenol 

Relevant articles and documents

Mediated electron transfer with monooxygenases - Insight in interactions between reduced mediators and the co-substrate oxygen

One of the most important obstacles to overcome in biocatalysis with monooxygenases is the enzyme's dependency on the costly redox cofactor NAD(P)H. Electrochemical regeneration systems, in which an electrode serves as electron donor, provide an alternative route to enzymatic redox reactions. Mediators are often used to accelerate electron transfer between electrode and enzyme. We investigated the mediated bioelectrochemical conversion of p-xylene to 2,5-dimethylphenol (2,5-DMP) by a P450 BM3 variant and were able to produce 2,5-DMP electrochemically. Due to the fact that mediator reduction is limited by the electrode surface a scale-up was performed. However, increasing the electrode surface area to reactor volume ratio led to a drastic increase in cathodic oxygen reduction, causing a drop in product formation. It was shown that reduced cobalt sepulchrate reacts with the co-substrate oxygen. Furthermore, the reportedly oxygen stable mediator [Cp*Rh(I)(bpy)H] + was compared to cobalt sepulchrate. While its turnover frequency is of comparable magnitude to cobalt sepulchrate when transferring the electrons between electrode and enzyme, using NADP+ as intermediary between the mediator and the enzyme significantly increased the mediator's turnover frequency. The rhodium mediator [Cp*Rh(I)(bpy)H]+ does not appear to be significantly more oxygen stable.

Method for synthesizing 2-5 -dimethylphenol

The invention discloses a method for synthesizing 2,5-dimethyl phenol. The method comprises the steps: utilizing 2,5-dimehtyl-benzenesulfonic acid as a raw material, supercritical distilled water as areaction medium, sodium hydroxide as a catalyst and oxygen as an oxidant; reacting to obtain a 2,5-dimethyl phenol crude product; finally, sequentially filtering, ethanol refining and filtering and drying to obtain a 2,5-dimethyl phenol pure product. The method disclosed by the invention utilizes the supercritical water to synthesize the 2,5-dimethyl phenol, so that the method is the most appropriate method in the present; reaction steps are reduced, and a technological process is shortened; thus, the environmental pollution problem is fundamentally solved, and no three wastes (waste water, waste gas and waste solid) are generated. Therefore, according to the method disclosed by the invention, the technology utilizing the supercritical water to synthesize the 2,5-dimethyl phenol has a very obvious effect.

Regioselectivity of Hydroxyl Radical Reactions with Arenes in Nonaqueous Solutions

The regioselectivity of hydroxyl radical addition to arenes was studied using a novel analytical method capable of trapping radicals formed after the first elementary step of reaction, without alteration of the product distributions by secondary oxidation processes. Product analyses of these reactions indicate a preference for o- over p-substitution for electron donating groups, with both favored over m-addition. The observed distributions are qualitatively similar to those observed for the addition of other carbon-centered radicals, although the magnitude of the regioselectivity observed is greater for hydroxyl. The data, reproduced by high accuracy CBS-QB3 computational methods, indicate that both polar and radical stabilization effects play a role in the observed regioselectivities. The application and potential limitations of the analytical method used are discussed.