2,3,6-TRICHLOROBENZOIC ACID

2,3,6-TRICHLOROBENZOIC ACID Property

Melting point:

126-127 °C(lit.)

Boiling point:

324.5±37.0 °C(Predicted)

Density 

1.5599 (estimate)

storage temp. 

Sealed in dry,Room Temperature

solubility 

soluble in Methanol

pka

1.25±0.25(Predicted)

color 

White to Light yellow to Light orange

Water Solubility 

7.70g/L(20 ºC)

Stability:

Stable under recommended storage conditions., Stable Under Recommended Storage C

CAS DataBase Reference

50-31-7(CAS DataBase Reference)

EPA Substance Registry System

2,3,6-Trichlorobenzoic acid (50-31-7)

Safety

Hazard Codes 

Xn,N

Risk Statements 

22-51/53

Safety Statements 

61

RIDADR 

UN 2811 6.1/PG 1

WGK Germany 

2

RTECS 

DH7700000

HS Code 

2916.39.7900

HazardClass 

9

Hazardous Substances Data

50-31-7(Hazardous Substances Data)

Toxicity

Acute oral LD50 for rats 1,500 mg/kg (Hartley and Kidd, 1987), 650 mg/kg (RTECS, 1985).

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Warning

Hazard statements

H302Harmful if swallowed

H411Toxic to aquatic life with long lasting effects

Precautionary statements

P273Avoid release to the environment.

2,3,6-TRICHLOROBENZOIC ACID Chemical Properties,Usage,Production

Chemical Properties

A solid.

Uses

An all-purpose, non-selective, pre-emergent and early post-emergent herbicide.

Uses

Systemic growth-regulator herbicide used for postemergence control of broad-leaved perennial and annual weeds in cereals and grass seed crops.

Definition

A substituted benzoic acid that is a potent synthetic auxin.

Hazard

Poison; moderately toxic.

Safety Profile

Poison by intraperitoneal route.Moderately toxic by ingestion and subcutaneous routes.When heated to decomposition it emits toxic fumes ofClí. Used as an herbicide.

Synthesis

The general procedure for the synthesis of 2,3,6-trichlorobenzoic acid from 2,3,6-trichlorobenzene was as follows: 2,3,6-trichlorobenzene was added to 100 mL of water, followed by the addition of 0.4 g of tetrabutylammonium chloride as a phase-transfer catalyst, and 63 g of potassium permanganate. The reaction mixture was heated to 50 °C for 6 hours. Upon completion of the reaction, the pH of the filtrate was adjusted to 3 with 5% hydrochloric acid solution (mass percent, as HCl), at which time a large amount of white solid precipitated. The precipitate was collected by filtration, washed with a small amount of water and dried to give 43.3 g of 2,3,6-trichlorobenzoic acid with 95% purity and 96% yield by HPLC.

Environmental Fate

Photolytic. Plimmer (1970) postulated that the irradiation of 2,3,6-trichlorobenzoic acid in methanol will undergo dechlorination forming 2,3-, 2,6- and 3,6-dichlorobenzoic acids. Further irradiation may yield 2- and 3-chlorobenzoic acids which may ultimately form benzoic acid (Plimmer, 1970).
Chemical/Physical. Reacts with alkalies and amines forming water-soluble salts.

References

[1] J. Appl. Chem. USSR (Engl. Transl.), 1980, vol. 53, # 12, p. 2076 - 2078
[2] Zhurnal Prikladnoi Khimii (Sankt-Peterburg, Russian Federation), 1980, vol. 53, # 12, p. 2737 - 2740
[3] Patent: CN105294419, 2016, A. Location in patent: Paragraph 0105; 0106
[4] Journal of the Chemical Society, 1951, p. 1208,1212
[5] Journal of the Chemical Society, 1902, vol. 81, p. 1335