2,4-Dihydroxybenzoic acid Property

Melting point:

208-211 °C (dec.) (lit.)

Boiling point:

237.46°C (rough estimate)

Density 

1.3725 (rough estimate)

vapor pressure 

0Pa at 25℃

refractive index 

1.6710 (estimate)

FEMA 

3798 | 2,4-DIHYDROXYBENZOIC ACID

Flash point:

200 °C

storage temp. 

Inert atmosphere,Room Temperature

solubility 

8g/l

form 

Crystalline Powder

pka

3.11, 8.55, 14.0(at 25℃)

color 

Cream to slightly beige or pink

Odor

at 100.00?%. mild phenolic

Water Solubility 

8 g/L (20 ºC)

Merck 

14,8157

JECFA Number

908

BRN 

1946213

InChIKey

UIAFKZKHHVMJGS-UHFFFAOYSA-N

LogP

0.98 at 23℃ and pH3.5

CAS DataBase Reference

89-86-1(CAS DataBase Reference)

NIST Chemistry Reference

2,4-Dihydroxybenzoic acid(89-86-1)

EPA Substance Registry System

2,4-Resorcylic acid (89-86-1)

Safety

Hazard Codes 

Xi

Risk Statements 

36/37/38

Safety Statements 

26-36-37/39

WGK Germany 

1

RTECS 

VH3708050

TSCA 

Yes

HS Code 

29182990

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Warning

Hazard statements

H315Causes skin irritation

H319Causes serious eye irritation

H335May cause respiratory irritation

Precautionary statements

P261Avoid breathing dust/fume/gas/mist/vapours/spray.

P264Wash hands thoroughly after handling.

P264Wash skin thouroughly after handling.

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

P304+P340IF INHALED: Remove victim to fresh air and Keep at rest in a position comfortable for breathing.

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

P405Store locked up.

2,4-Dihydroxybenzoic acid Chemical Properties,Usage,Production

Uses

2,4-Dihydroxybenzoic acid is a useful synthetic intermediate. An organic building block for plastics and rubber products.

Toxicity

GRAS (FEMA).

Usage limits

FEMA (mg/kg): cold drink: 450; Meat, dairy, processed vegetables, 100; fudge, gel, pudding, snack food, beverages, breakfast cereals, fats, cheeses, poultry products, fish, spices, sweet sauce, dairy products, meat soup, fruit ice Egg products, jams, jelly, rehydrated vegetables, 500; soup: 250; jelly sugar: 3333; instant coffee and tea: 12.5; sugar substitute: 12500; seasoning spices: 25000.

Chemical properties

It appears as white needle crystal. It will contain crystal water upon crystallization from the water. It appears as an anhydride at 100 ℃. Melting point 218-219 ° C (it has a melting point of 213 ° C upon thermal shock). Soluble in hot water, ethanol, ether. Cooking in water, acid or salt solution will remove carbon dioxide. It exhibits red color upon reaction with ferric chloride.

Application

• The product has the chemical properties of both resorcinol and salicylic acid. It can be used in chemical reagents for colorimetric determination of iron, titanium and other elements; for organic synthesis, it is mainly used for dyes and pharmaceutical intermediates. 2, 4-dihydroxybenzoic acid is a major raw material during the production of acidic medicated pink 3BM, which consumes 157 kg per ton of dye (by 100%).
• Used as a dye intermediate, medicine and reagents
• Used as dyes, pharmaceuticals, pesticide intermediates

Preparation

It is derived from the hydroxylation of resorcinol.

Chemical Properties

cream to slightly beige or pink crystalline powder

Chemical Properties

Dihydroxybenzoic acid is a colorless solid and is used as a flavor modifier.

Occurrence

Reported present in avocados, beer, red wine, roast coffee, sherry, smoked sausage and white wine

Uses

2,4-Dihydroxybenzoic acid is used in Intermediates, Plasticizers, Plastic and Rubber Products, a organic building block.

Uses

Intermediate for dyestuffs and drugs; spot test reagent for iron.

Preparation

Prepared from resorcinol and potassium bicarbonate in glycerol or water by heating and passing carbon dioxide through the mixture.

Purification Methods

Crystallise the acid from water. [Beilstein 10 IV 1420.]