Chemical Properties
colourless to light yellow liquid
Definition
ChEBI: A cresol with the methyl substituent at position 3. It is a minor urinary metabolite of toluene.
General Description
Colorless liquid with a sweet tarry odor. Sinks and mixes slowly with water.
Reactivity Profile
M-CRESOL(108-39-4) is sensitive to air, light and heat. M-CRESOL(108-39-4) is also hygroscopic. This chemical can react vigorously with strong oxidizers and strong bases. M-CRESOL(108-39-4) reacts violently with nitric acid, oleum, chlorosulfonic acid, metals and strong acids. If the water content is below approximately 0.3% and the temperature above 248° F, the corrosion of aluminum and its alloys may occur violently. M-CRESOL(108-39-4) will attack some forms of plastics, coatings and rubber.
Air & Water Reactions
Water soluble.
Hazard
Questionable carcinogen.
Health Hazard
INHALATION: Mucosal irritation and systemic poisoning EYES: Intense irritation and pain, swelling of conjunctiva, and corneal damage may occur. SKIN: Intense burning, loss of feeling, wrinkling, white discoloration, and softening. Gangrene may occur. INGESTION: Burning sensation in mouth and esophagus. Vomiting may result. Acute exposure by all routes may cause muscular weakness, gastroenteric disturbances, severe depression, collapse. Effects are primarily on CNS and edema of lungs. Injury of spleen and pancreas may occur.
Potential Exposure
Cresol is used as a disinfectant and fumigant; as an ore flotation agent, and as an intermediate in the manufacture of chemicals, dyes, plastics, and antioxidants. A mixture of isomers is generally used; the concentrations of the components are determined by the source of the cresol.
First aid
If this chemical gets into the eyes, remove any contact lenses at once and irrigate immediately for at least 15 minutes, occasionally lifting upper and lower lids. Seek medical attention immediately. If this chemical contacts the skin, remove contaminated clothing and wash immediately with soap and water. Seek medical attention immediately. If this chemical has been inhaled, remove from exposure, begin rescue breathing (using universal precautions, including resuscitation mask) if breathing has stopped and CPR if heart action has stopped. Transfer promptly to a medical facility. When this chemical has been swallowed, get medical attention. Give large quantities of water and induce vomiting. Do not make an unconscious person vomit. Medical observation is recommended for 24 to 48 hours after breathing overexposure, as pulmonary edema Cresols 931 may be delayed. As first aid for pulmonary edema, a doctor or authorized paramedic may consider administering a drug or other inhalation therapy
Shipping
UN2076 Cresols, liquid, Hazard class: 6.1; Labels: 6.1-Poisonous materials, 8-Corrosive material. UN3455 Cresols, solid, Hazard class: 6.1; Labels: 6.1- Poisonous materials, 8-Corrosive material.
Incompatibilities
Vapors may form explosive mixture with air. Incompatible with strong acids; oxidizers, alkalies, aliphatic amines; amides, chlorosulfonic acid; oleum. Decomposes on heating, producing strong acids and bases, causing fire and explosion hazard. Liquid attacks some plastics and rubber. Attacks many metals.
Waste Disposal
Wastewaters may be subjected to biological treatment. Concentrations may be further reduced by ozone treatment. High concentration wastes may be destroyed in special waste incinerators.
Occurrence
Reported found in beer, coffee, egg, grape, Oriental tobacco, roasted barley, rum, sherry and whiskey.
Preparation
One process involving butylation and separation and followed by dealkylation produces m-cresol and ditertiary butyl
p-cresol. From m, p-cresol (which is the main product of the recovery process) pure m-cresol can be obtained by extraction.
Production Methods
The cresols (cresylic acids) are methyl phenols and generally
appear as a mixture of isomers. m-Cresol is prepared
from m-toluic acid or obtained from coal tar or petroleum
(352, 355, 356). Crude cresol is obtained by distilling
“gray phenic acid” at a temperature of ~180–201°C. The
m-cresol may be separated from the crude or purified mixture
by repeated fractional distillation in vacuo. It can also be
prepared synthetically by diazotization of the specific toluidine
or by fusion of the corresponding toluenesulfonic acid
with sodium hydroxide.
Aroma threshold values
Aroma characteristics at 1.0%: phenolic, spicy eugenol-like, medicinal, smoky powdery with a leatherlike
note.
Taste threshold values
Taste characteristics at 2 ppm: phenolic, smoky, balsamic, medicinal and spicy eugenol-like
Flammability and Explosibility
Notclassified
Carcinogenicity
m-Cresol has induced a few papillomas
but no carcinomas in tumor studies.
Purification Methods
Separation of the m-and p-cresols requires chemical methods, such as conversion to their sulfonates [Brüchner Anal Chem 75 289 1928]. An equal volume of H2SO4 is added to m-cresol, stirred with a glass rod until solution is complete. Heat for 3hours at 103-105o. Dilute carefully with 1-1.5 volumes of water, heat to boiling point and steam distil until all unsulfonated cresol has been removed. Cool and extract the residue with ether. Evaporate the solution until the boiling point reaches 134o and steam distil off the m-cresol. Another purification method involves distillation, fractional crystallisation from the melt, then redistillation. Free from p-cresol by solution in glacial acetic acid and bromination by about half of an equivalent amount of bromine in glacial acetic acid. The acetic acid is distilled off, then fractional distillation of the residue under vacuum gives bromocresols from which 4-bromo-m-cresol is obtained by crystallisation from hexane. Addition of the bromocresol in glacial acetic acid slowly to a reaction mixture of HI and red phosphorus or (more smoothly) of HI and hypophosphorus acid, in glacial acetic acid, at reflux, removes the bromine. After an hour, the solution is distilled at atmospheric pressure until layers are formed. Then it is cooled and diluted with water. The cresol is extracted with ether, washed with water, NaHCO3 solution and again with water, dried with a little CaCl2 and distilled [Baltzly et al. J Am Chem Soc 77 2522 1955]. The 3,5-dinitrobenzoate (prepared with 3,5-dinitrobenzoyl chloride in dry pyridine, and recrystallised from EtOH or aqueous Me2CO) has m 165o. [Beilstein 6 IV 2035.]