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, chemical formula: (CH3)2C6H3OH.) is a chemical compound as one of the six isomers of xylenol. It is found in alcoholic beverages, coffee and whisky. It is a kind of flavoring agent belonging to the family of Ortho Cresols. One of its applications is for the synthesis of Mexilethine. It has important industrial importance, e.g. for the manufacture of antioxidants. It is also a monomer for the poly (p-phenylene oxide) engineering resins through carbon-oxygen oxidative coupling. It is traditionally extracted from the coal tar.

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

Chemical Properties

2,5-Xylenol has a creosote, sweet, medicinal taste.

Occurrence

Reported found in coffee, smoked fatty fish, processed lean fish, malt whiskey, Scotch blended whiskey, katsuobushi (dried bonito) and kumazasa (Sasa albo-marginata).

Uses

Used to make phenolic resins and (in isomeric mixtures) as an antioxidant for lubricating oils, gasoline, and elastomers. Also used as perfuming agents.

Taste threshold values

Taste characteristics at 10 ppm: musty, chemical, stringent and phenolic.

General Description

Colorless to off-white crystalline solid. Odor threshold concentration 0.4 mg/L. Taste threshold concentration 0.5 mg/L.

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

• 578-58-5 2-methylmethoxybenzene 
• 95-78-3 2,5-Dimethylaniline 
• 102741-59-3 2,5-dimethylphenyl N-benzoylglycinate 
• 34202-99-8 2,5-dimethylphenylthallium bis(trifluoroacetate) 
• 1122-42-5 2-iodo-p-xylene 
• 7446-70-0 aluminium trichloride 
• 14845-35-3 2,5-dimethyl-cyclohex-2-enone 
• 7705-08-0 iron(III) chloride 
• 64-19-7 acetic acid 
• 7647-01-0 hydrogenchloride 
• 109-95-5 ethyl nitrite 
• 64-17-5 ethanol 
• 526-75-0 2,3-Dimethylphenol 
• 860696-56-6 (2-carboxy-6-hydroxy-4-methyl-phenyl)-acetic acid 

Downstream Products

• 93-86-7 2-(2,5-dimethylphenoxy)ethan-1-ol 
• 68097-96-1 1-<(4-Hydroxy-3,6-dimethyl-phenyl)-methyl>-piperidin 
• 29053-91-6 2,5-dimethyl-4-morpholin-4-ylmethyl-phenol 
• 859051-86-8 N²-[2-(2,5-dimethyl-phenoxy)-1,1-dimethyl-ethyl]-1,1-dimethyl-ethanediyldiamine 
• 4673-48-7 3-(2,5-dimethyl-phenoxy)-propionic acid 
• 10496-93-2 4-Hydroxy-2,5-dimethylbenzenemethanol 
• 15367-95-0 silicic acid tetrakis-(2,5-dimethyl-phenyl ester) 
• 53414-14-5 1,1,1-trichloro-2,2-bis-(4-hydroxy-2,5-dimethyl-phenyl)-ethane 
• 85231-15-8 4-formyl-2,5-dimethylphenol 
• 1666-04-2 2-hydroxy-3,6-dimethylbenzaldehyde 
• 93816-50-3 1,4,5,8-Tetramethyl-acridin 
• 110047-13-7 carbamic acid-(2,5-dimethyl-phenyl ester) 
• 114166-34-6 allophanic acid-(2,5-dimethyl-phenyl ester) 
• 584-53-2 (2-chloro-1,1,2-trifluoro-ethyl)-(2,5-dimethyl-phenyl)-ether 

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.

Environmentally friendly preparation method for 2,5-dimethylphenol

The invention relates to an environmentally friendly preparation method for 2,5-dimethylphenol. The preparation method uses 2,5-dimethyl isopropylbenzene as an initial raw material, and obtains 2,5-(dimethyl)phenyl isopropyl peroxide through air or oxygen oxidation under the action of a solvent and a composite catalyst; and 2,5-dimethylphenol can be obtained through direct rearrangement of the obtained peroxide under an acidic condition. The preparation method is cheap and easy in raw material obtaining, convenient in operation, good in reaction selectivity and high in product yield; and by-product acetone can be produced while the 2,5-dimethylphenol is prepared, so that the preparation method is high in reaction atomic economy, less in the three wastes (waste gas, waste water and industrial residue), and low in product cost.