3,4-Dimethylphenol Property

Melting point:

65-68 °C

Boiling point:

227 °C(lit.)

Density 

1,138 g/cm³

vapor pressure 

0.475-130Pa at 25-66.2℃

refractive index 

1.5442

FEMA 

3596 | 3,4-XYLENOL

Flash point:

61 °C

storage temp. 

Store below +30°C.

solubility 

Chloroform (Slightly), Ethyl Acetate (Slightly), Methanol (Slightly)

pka

pK1:10.32 (25°C)

form 

Crystalline Powder

color 

Off-white to pale cream

Odor

DIMETHYLPHENOL slightly smoky and earthy character provides nice roasted notes to seafood, mushroom and coffee flavors.flat dry

Odor Type

dry

explosive limit

1.4%(V)

Water Solubility 

SLIGHTLY SOLUBLE

Merck 

14,10082

JECFA Number

708

BRN 

1099267

Exposure limits

ACGIH: TWA 1 ppm

InChIKey

YCOXTKKNXUZSKD-UHFFFAOYSA-N

LogP

2.23 at 25℃

CAS DataBase Reference

95-65-8(CAS DataBase Reference)

NIST Chemistry Reference

Phenol, 3,4-dimethyl-(95-65-8)

EPA Substance Registry System

3,4-Dimethylphenol (95-65-8)

Safety

Hazard Codes 

T,N

Risk 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 

ZE6300000

TSCA 

Yes

HazardClass 

6.1

PackingGroup 

II

HS Code 

29071400

Hazardous Substances Data

95-65-8(Hazardous Substances Data)

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Danger

Hazard statements

H314Causes severe skin burns and eye damage

H411Toxic to aquatic life with long lasting effects

Precautionary statements

P260Do not breathe dust/fume/gas/mist/vapours/spray.

P273Avoid release to the environment.

P280Wear protective gloves/protective clothing/eye protection/face protection.

P303+P361+P353IF ON SKIN (or hair): Remove/Take off Immediately all contaminated clothing. Rinse SKIN with water/shower.

P305+P351+P338IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing.

3,4-Dimethylphenol Chemical Properties,Usage,Production

Description

3,4-methylphenol (also 3,4-xylenol) has a flat, dry odor. It can be used as a flavoring agent without safety concern at current levels of intake. 3,4-dimethylphenol is used as an agent in the spectrophotometric method to determine nitrate in plants, soils, and water. It is also used to produce adhesive/sealant and resins as negative photoresist for electroplating.

References

[1] R. R. Elton-Bott, A modified spectrophotometric method for nitrate in plants, soils and water by nitration of 3,4-dimethylphenol, Analytica Chimica Acta, 1977, vol. 90, 215-221
[2] George A. Burdock, Fenaroli’s Handbook of Flavor Ingredients, Sixth Edition, 2010
[3] Chia L. Wang, John Davis, Bryan Lienke, Polyurethane systems having non-sag paintability and primerless adhesion on concrete, Patent, 2012
[4] Yasuo Masuda, Yasushi Washio, Koji Saito, Method of forming plated product using negative photoresist composition and photosensitive composition used therein, Patent, 2012

Chemical Properties

YELLOW TO BROWNISH CRYSTALLINE MASS

Occurrence

Reported found in coffee, tomato, parmesan and romano cheese, smoked fatty fish, white wine, katsuobushi (dried bonito) and wood vinegar.

Uses

Applications of 3,4-dimethylphenol:

• It can react with ethyl cinnamates in trifluoroacetic acid to form the corresponding dihydrocoumarin derivatives.
• Bromination of 3,4-dimethylphenol using bromine can lead to 6-bromo-3,4-dimethylphenol.
• It can react with 1-fluoro-4-chloromethyl-1,4-diazoniabicyclo[2.2.2]octane bis(tetrafluoro-borate) (Selectfluor^? F-TEDA-BF₄) to form 4-fluoro-3,4-dimethylcyclohexa-2,5-dienone.

Definition

ChEBI: 3,4-xylenol is a member of the class of phenols that is phenol substituted by methyl groups at positions 3 and 4. It derives from a hydride of an o-xylene.

Aroma threshold values

Detection: 1.2 ppm

General Description

Colorless to light tan crystalline powder or solid. Odor threshold 1.2 mg/L. Taste threshold 0.05 mg/L.

Air & Water Reactions

Hygroscopic. Insoluble in water.

Reactivity Profile

3,4-Dimethylphenol is incompatible with bases, acid chlorides, acid anhydrides, and oxidizing agents. 3,4-Dimethylphenol corrodes steel, brass, copper, and copper alloys.

Fire Hazard

Flash point data for 3,4-Dimethylphenol are not available. 3,4-Dimethylphenol is probably combustible.

Purification Methods

Heat 3,4-xylenol with an equal weight of conc H2SO4 at 103-105o for 2-3hours, then dilute it with four volumes of water, reflux it for 1hour, and either steam distil or extract it repeatedly with diethyl ether after cooling to room temperature. The steam distillate is also extracted and evaporated to dryness. (The purification process depends on the much slower sulfonation of 3,4-dimethylphenol than most of its likely contaminants.). It can also be crystallised from water, hexane or pet ether, and sublimed in a vacuum. [Kester Ind Eng Chem (Anal Ed) 24 770 1932, Bernasconi & Paschalis J Am Chem Soc 108 29691986, Beilstein 6 IV 3099.]