Catechol Chemical Properties

Melting point:

100-103 °C (lit.)

Boiling point:

245 °C (lit.)

Density 

1,371 g/cm³

vapor density 

3.8 (vs air)

vapor pressure 

1 mm Hg ( 75 °C)

refractive index 

1.6120 (estimate)

Flash point:

279 °F

storage temp. 

Store below +30°C.

solubility 

430g/l

form 

Crystalline Flakes

pka

9.85(at 20℃)

color 

white to faintly beige

PH

6 (100g/l, H2O, 20℃)

explosive limit

1.97%(V)

Water Solubility 

430 g/L (20 ºC)

Sensitive 

Air & Light Sensitive

Merck 

14,7999

BRN 

471401

Exposure limits

TLV-TWA 5 ppm (～22 mg/m³) (ACGIH). .

Stability:

Stable. Substances to be avoided include acid chlorides, acid anhydrides, bases, oxidizing agents, nitric acid. Light sensitive; may discolour on exposure to air. Combustible.

LogP

0.93

CAS DataBase Reference

120-80-9(CAS DataBase Reference)

NIST Chemistry Reference

1,2-Benzenediol(120-80-9)

IARC

2B (Vol. 15, Sup 7, 71) 1999

EPA Substance Registry System

Catechol (120-80-9)

Safety Information

Hazard Codes 

Xn

Risk Statements 

21/22-36/38-68-43

Safety Statements 

22-26-37-39

RIDADR 

UN 2811 6.1/PG 3

WGK Germany 

2

RTECS 

UX1050000

TSCA 

Yes

HS Code 

2907 29 00

HazardClass 

6.1

PackingGroup 

III

Hazardous Substances Data

120-80-9(Hazardous Substances Data)

Toxicity

LD50 in mice (mg/kg): 260 orally; 190 i.p. (Lehman)

MSDS

• Language:English Provider:ACROS
• Language:English Provider:SigmaAldrich
• Language:English Provider:ALFA

Catechol Usage And Synthesis

Chemical Properties

Off-white powder

Chemical Properties

Catechol also called Pyrocatechol is a white crystalline solid. Turns brown on contact with light and air.

Uses

In photography; dyeing fur; as reagent.

Uses

Catechol is used in photography, in dyeing fur, and as a topical antiseptic.

Uses

In the manufacture of rubber antioxidants and monomer inhibitors to stop radical polymerization; in dyes, as a photographic developer; in formulations for pharmaceuticals, perfumes, inks, and insecticides

Production Methods

Catechol may be obtained by the fusion of o-phenolsulfonic acid with alkali, by heating chorophenol with a solution of sodium hydroxide at 200°C in an autoclave, or by cleavage of the methyl ether group of guaiacol (obtained from beechwood tar) with hydriodic acid.

Definition

A colourless crystalline PHENOL containing two hydroxyl groups. It is used in photographic developing.

Synthesis Reference(s)

The Journal of Organic Chemistry, 45, p. 4275, 1980 DOI: 10.1021/jo01310a003

General Description

Solid; white; odorless. Sinks and mixes with water.

Air & Water Reactions

Turns brown on exposure to air and light, especially when moist. Water soluble. Aqueous solutions soon turn brown on exposure to air and light.

Reactivity Profile

POISONOUS GASES MAY BE PRODUCED WHEN HEATED. Pyrocatechol may form toxic fumes at high temperatures. [USCG, 1999]. Pyrocatechol can react with acid chlorides, acid anhydrides, bases and oxidizing agents. Pyrocatechol reacts violently on contact with concentrated nitric acid. Pyrocatechol acts as a reducing agent .

Hazard

Strong irritant. Toxic by skin absorption. Eye and upper respiratory tract irritant, and der- matitis. Possible carcinogen.

Health Hazard

DUST: Irritating to eyes, nose and throat. If inhaled will cause coughing or difficult breathing. SOLID: Will burn skin and eyes. Harmful if swallowed.

Health Hazard

Acute oral and percutaneous toxicity of pyrocatechol is greater than that of phenol; inhalation toxicity is less than that of phenol. The toxic symptoms include weakness, muscular pain, dark urine, tremor, dyspnea, and convulsions. Large amounts can produce degenerative changes in renal tubules. Large doses can cause death due to respiratory failure. Skin contact can cause eczematous dermatitis.
LD50 value, oral (rats): 260 mg/kg
LD50 value, skin (rabbits): 800 mg/kg.

Fire Hazard

Combustible. POISONOUS GASES MAY BE PRODUCED WHEN HEATED. May form toxic fumes at high temperatures.

Flammability and Explosibility

Non flammable

Safety Profile

Poison by ingestion, subcutaneous, intraperitoneal, intravenous, and parenteral routes. Moderately toxic by skin contact. Experimental reproductive effects. Can cause dermatitis on skin contact. An allergen. Human mutation data reported. Questionable carcinogen. Systemic effects sirmlar to those of phenol. Combustible when exposed to heat or flame; can react vigorously with oxidizing materials. Hypergolic reaction with concentrated nitric acid. To fight fire, use water, CO2, dry chemical. When heated to decomposition it emits acrid smoke and irritating fumes. See also PHENOL.

Potential Exposure

Used as a chemical intermediate; pharmaceutical and veterinary drug; as an antiseptic; in photography; in dyestuff manufacture and application. It is also used in electroplating, in the formulation of specialty inks; in antioxidants; and light stabilizers.

Carcinogenicity

Catechol has been extensively studied for its role in carcinogenesis of the rat glandular stomach; it was concluded that pyrocatechol is carcinogenic. When rats and mice were administered 0.8% pyrocatechol in their feed for life, there was an increase in glandular stomach adenocarcinoma in both male and female rats. Pyrocatechol also caused hyperplasia of the glandular stomach in both rats and mice, a mechanism that could cause promotion of carcinogen-initiated cells; no effects on the esophagus or urinary bladder were reported. There were no cutaneous neoplasms when pyrocatechol was applied in dermal studies. Catechol may be classified as a cocarcinogen because it enhanced the number and/or incidence of lesions in the stomach induced by several carcinogenic nitrosamines and cutaneous neoplasms when administered dermally together with several carcinogens.

Shipping

UN 2811 Toxic solids, organic, n.o.s., Hazard Class: 6.1; Labels: 6.1-Poisonous materials, Technical Name Required.

Purification Methods

Crystallise catechol from *benzene or toluene and sublime it in vacuo. [Rozo et al. Anal Chem 58 2988 1986, Beilstein 6 IV 5557.]

Incompatibilities

Incompatible with oxidizers (chlorates, nitrates, peroxides, permanganates, perchlorates, chlorine, bromine, fluorine, etc.); contact may cause fires or explosions. Keep away from alkaline materials, strong bases, strong acids, oxoacids, epoxides.

Catechol(120-80-9)Related Product Information

• Hydroquinone
• tert-Butylhydroquinone
• 4-tert-Butylcatechol
• 3,4,5-Trimethoxyphenylacetonitrile
• 3,4-Dimethoxycinnamonitrile
• CATECHOLBORANE
• (3,4-Dimethoxyphenyl)acetonitrile
• Alizarin
• 3,4-DIMETHOXYBENZOYL CHLORIDE
• 3,4,5-Trimethoxybenzonitrile
• Pyrocatechol Violet
• 4-Methylcatechol
• Resorcinol
• Colchicine
• Catechol
• 3,4,5-Trimethoxybenzoyl chloride
• 4-HYDROXY-3-METHOXYPHENYLACETONITRILE
• ALIZARIN COMPLEXONE