Toluene

The name Toluene (CAS NO.108-88-3) was derived from the older name toluol, which refers to tolu balsam, an aromatic extract from the tropical Colombian tree Myroxylon balsamum, from which it was first isolated. It was originally named by J?ns Jakob Berzelius.

Community Right-To-Know List. Reported in EPA TSCA Inventory. EPA Genetic Toxicology Program.

OSHA PEL: TWA 100 ppm; STEL 150 ppm
ACGIH TLV: TWA 50 ppm (skin); Not Classifiable as a Human Carcinogen; BEI: 1.6 g/g creatinine of hippuric acid in urine at end of shift; 0.05 mg/L toluene in venous blood prior to last shift of workweek; BEI: BEI: 0.05 mg/L toluene in venous blood prior to last shift of work ek; 0.5 mg/L o-cresol in urine at end of shift
DFG MAK: 50 ppm (190 mg/m³); BAT: 340 μg/dL in blood at end of shift
NIOSH REL: (Toluene) TWA 100 ppm; CL 200 ppm/10M
DOT Classification:  3; Label: Flammable Liquid

For occupational chemical analysis use NIOSH: Hydrocarbons, Aromatic, 1501; Hydrocarbons, Bp: 36–126°C, 1500.

Toluene, also called Methylbenzene, is a colorless, flammable liquid with a benzenelike odor. It is insoluble in water, but miscible with benzene, alcohol, ether and other organic solvents. Toluene was first isolated as aromatic extract from the tropical Colombian tree Myroxylon balsamum. In chemical, it is a mono-substituted benzene derivative commonly used as an industrial solvent for the manufacturing of paints, chemicals, pharmaceuticals, and rubber. And it is not only an important organic solvent, but also dissolving a number of notable inorganic chemicals such as sulfur.

In the presence of strong oxidizer (potassium permanganate, hydrogen nitrate, etc), Toluene is oxidized to benzoic acid. Benzaldehyde can be obtained by toluene and manganese dioxide from oxidation below 40 °C in the presence of sulfuric acid. More over, toluene reacts vigorously with allyl chloride or other alkyl halides even at minus 70° C in the presence of ethyl aluminum dichloride or ethyl aluminum sesquichloride.

Preparation: Toluene can be produced by many methods.
1. It is derived from coal tar, and commercial grades usually contain small amounts of benzene as an impurity.

2. It can be obtained by benzene from Friedel–Crafts reaction. Benzene reacts with CH₃⁺ and AlCl₄^- which are got by CH₃Cl and AlCl₃ to form toluene. In this reaction, the AlCl³ is used as catalyst.
CH₃Cl + AlCl₃ → CH₃⁺ + AlCl₄^-
C₆H₅H + CH₃+ + AlCl₄^- → C₆H₅CH₃ + HCl + AlCl₃

3. It can be obtained by cresol from distillation with zinc dust.
C₆H₄CH₃OH (cresol) + Zn → C₆H₅CH₃ (toluene) + ZnO

4. It can be obtained by bromobenzene from Wurtz-Fittig reaction. When bromobenzene and methyl bromide react with sodium metal in dry ether solution, toluene is obtained.
C₆H₅Br + CH₃Br + 2Na → C₆H₅CH₃ + 2NaBr

5. It can be obtained by decarboxylation from toluic acid. Heat the sodium salt of toluic acid (o-, m-, p-) with soda lime, then toluene is synthesized.
C₆H₄CH₃COONa (sodium toluate) + NaOH → C₆H₅CH₃ (toluene) + Na₂CO₃

Uses: 1. Toluene is not only widely used as organic solvent, but also used as raw material to synthetize pharmaceuticals, paints, resins, dyes, explosives, pesticides ansd so on. Moreover, it used as standard material for chromatography and analytical reagent.

2. Toluene is also used as raw material in production of benzene and many other chemical products. For example: it can react with tert-butyl hydroperoxide to get benzyl-tert-butyl peroxide. This reaction needs reagent RuIII-Montmorillonite K10 and solvent acetonitrile by heating. The reaction time is 4 hours. The yield is 60%.

3. It is used as leaching agent of plant components. Used in internal combustion engines, toluene can be used as an octane booster in gasoline fuels. And it has also been used as a coolant for its good heat transfer capabilities in sodium cold traps used in nuclear reactor system loops.

Safety: Toluene is toxic by inhalation, in contact with skin and if swallowed. And it also has danger of very serious irreversible effects. The vapours of toluene may cause drowsiness and dizziness. If you want to contact this product, you must wear suitable protective clothing and gloves. In case of accident or if you feel unwell, seek medical advice immediately (show the label whenever possible.) If swallowed, do not induce vomitting; seek medical advice immediately and show this container or label. So toluene should be sealed in the container and stored in the cool and dry place which must be away from oxidant.

Structure conversion:
1.Smiles:c1(ccccc1)C
2.InChI:InChI=1S/C7H8/c1-7-5-3-2-4-6-7/h2-6H,1H3

Toxicity:  

Organism	Test Type	Route	Reported Dose (Normalized Dose)	Effect	Source
frog	LDLo	subcutaneous	920mg/kg (920mg/kg)	AUTONOMIC NERVOUS SYSTEM: OTHER (DIRECT) PARASYMPATHOMIMETIC BEHAVIORAL: CONVULSIONS OR EFFECT ON SEIZURE THRESHOLD BEHAVIORAL: CHANGES IN MOTOR ACTIVITY (SPECIFIC ASSAY)	Naunyn-Schmiedeberg's Archiv fuer Experimentelle Pathologie und Pharmakologie. Vol. 130, Pg. 250, 1928.
guinea pig	LCLo	inhalation	1600ppm (1600ppm)	BEHAVIORAL: GENERAL ANESTHETIC BEHAVIORAL: SOMNOLENCE (GENERAL DEPRESSED ACTIVITY) BEHAVIORAL: IRRITABILITY	Journal of Industrial Hygiene. Vol. 10, Pg. 261, 1928.
guinea pig	LD50	intraperitoneal	500mg/kg (500mg/kg)		Neurotoxicology. Vol. 2, Pg. 567, 1981.
human	LDLo	oral	50mg/kg (50mg/kg)		Gekkan Yakuji. Pharmaceuticals Monthly. Vol. 22, Pg. 883, 1980.
human	TCLo	inhalation	200ppm (200ppm)	BRAIN AND COVERINGS: RECORDINGS FROM SPECIFIC AREAS OF CNS BLOOD: CHANGES IN BONE MARROW NOT INCLUDED ABOVE BEHAVIORAL: ANTIPSYCHOTIC	JAMA, Journal of the American Medical Association. Vol. 123, Pg. 1106, 1943.
mammal (species unspecified)	LC50	inhalation	30gm/m3 (30000mg/m3)		Gigiena Truda i Professional'nye Zabolevaniya. Labor Hygiene and Occupational Diseases. Vol. 32(10), Pg. 25, 1988.
mammal (species unspecified)	LD50	oral	4gm/kg (4000mg/kg)		Gigiena Truda i Professional'nye Zabolevaniya. Labor Hygiene and Occupational Diseases. Vol. 32(10), Pg. 25, 1988.
mammal (species unspecified)	LDLo	intraperitoneal	1750mg/kg (1750mg/kg)	BEHAVIORAL: MUSCLE CONTRACTION OR SPASTICITY) LUNGS, THORAX, OR RESPIRATION: OTHER CHANGES	American Journal of Hygiene. Vol. 7, Pg. 276, 1927.
man	LDLo	oral	719uL/kg (0.719mL/kg)	CARDIAC: OTHER CHANGES LUNGS, THORAX, OR RESPIRATION: ACUTE PULMONARY EDEMA LIVER: OTHER CHANGES	Forensic Science International. Vol. 41, Pg. 255, 1989.
man	TCLo	inhalation	100ppm (100ppm)	BEHAVIORAL: "HALLUCINATIONS, DISTORTED PERCEPTIONS" BEHAVIORAL: CHANGES IN MOTOR ACTIVITY (SPECIFIC ASSAY) BEHAVIORAL: CHANGES IN PSYCHOPHYSIOLOGICAL TESTS	Work, Environment, Health. Vol. 9, Pg. 131, 1972.
mouse	LC50	inhalation	400ppm/24H (400ppm)		Neurotoxicology. Vol. 2, Pg. 567, 1981.
mouse	LD50	intraperitoneal	59mg/kg (59mg/kg)		Neurotoxicology. Vol. 2, Pg. 567, 1981.
mouse	LD50	subcutaneous	2250mg/kg (2250mg/kg)		Neurotoxicology. Vol. 8, Pg. 237, 1987.
mouse	LD50	unreported	2gm/kg (2000mg/kg)		Gigiena i Sanitariya. For English translation, see HYSAAV. Vol. 45(12), Pg. 64, 1980.
rabbit	LCLo	inhalation	55000ppm/40M (55000ppm)		Journal of Industrial Hygiene and Toxicology. Vol. 26, Pg. 69, 1944.
rabbit	LD50	skin	14100uL/kg (14.1mL/kg)		American Industrial Hygiene Association Journal. Vol. 30, Pg. 470, 1969.
rabbit	LDLo	intravenous	130mg/kg (130mg/kg)		Haematologica. Vol. 58, Pg. 491, 1973.
rat	LC50	inhalation	49gm/m3/4H (49000mg/m3)		Gigiena Truda i Professional'nye Zabolevaniya. Labor Hygiene and Occupational Diseases. Vol. 32(10), Pg. 23, 1988.
rat	LD50	intraperitoneal	1332mg/kg (1332mg/kg)		Environmental Research. Vol. 40, Pg. 411, 1986.
rat	LD50	intravenous	1960mg/kg (1960mg/kg)		Medicina del Lavoro. Industrial Medicine. Vol. 54, Pg. 486, 1963.
rat	LD50	oral	636mg/kg (636mg/kg)		Neurotoxicology. Vol. 2, Pg. 567, 1981.
rat	LD50	unreported	6900mg/kg (6900mg/kg)		Gigiena i Sanitariya. For English translation, see HYSAAV. Vol. 45(12), Pg. 64, 1980.