2,5-Dichlorobenzoic acid CAS NO.50-79-3

Product Name:    2,5-Dichlorobenzoic acid
Synonyms:    2,5-DICHLOROBENZOIC ACID;RARECHEM AL BO 0355;2,5-dichloro-benzoicaci;1,2-DICHLOROBENZENE PESTANAL;2,5-Dichlorobenzoic acid, 98+%;Irsogladine Impurity S;2,5-Dichlorobenzoic a;Benzoic acid, 2,5-dichloro-
CAS:    50-79-3
MF:    C7H4Cl2O2                   
MW:    191.01       
EINECS:    200-065-7                             
Mol File:    50-79-3.mol              

2,5-Dichlorobenzoic acid Chemical Properties
Melting point     151-154 °C (lit.)
Boiling point     301 °C (lit.)
density     1.4410 (rough estimate)
refractive index     1.4590 (estimate)
Fp     300-302°C
storage temp.     Store below +30°C.
solubility     0.8g/l
pka    2.51±0.25(Predicted)
form     Powder
color     White to beige
Water Solubility     <0.1 g/100 mL at 19 ºC
BRN     973353
Stability:    Stable.
CAS DataBase Reference    50-79-3(CAS DataBase Reference)
NIST Chemistry Reference    Benzoic acid, 2,5-dichloro-(50-79-3)
EPA Substance Registry System    Benzoic acid, 2,5-dichloro- (50-79-3)
Safety Information
Hazard Codes     Xi
Risk Statements     36/37/38
Safety Statements     26-36-24/25
WGK Germany     3
RTECS     DG6825000
TSCA     Yes
HS Code     29163900
MSDS Information
Provider    Language
2,5-Dichlorobenzoic acid    English
SigmaAldrich    English
ACROS    English
ALFA    English
2,5-Dichlorobenzoic acid Usage And Synthesis
Chemical Properties    white crystalline powder
Definition    ChEBI: A chlorobenzoic acid that is benzoic acid in which the ring hydrogens at positions 2 and 5 are substituted by chloro groups.
General Description    Needles (from water) or white powder.
Air & Water Reactions    Insoluble in water.
Reactivity Profile    Carboxylic acids donate hydrogen ions if a base is present to accept them. They react in this way with all bases, both organic (for example, the amines) and inorganic. Their reactions with bases, called "neutralizations", are accompanied by the evolution of substantial amounts of heat. Neutralization between an acid and a base produces water plus a salt. Carboxylic acids with six or fewer carbon atoms are freely or moderately soluble in water; those with more than six carbons are slightly soluble in water. Soluble carboxylic acid dissociate to an extent in water to yield hydrogen ions. The pH of solutions of carboxylic acids is therefore less than 7.0. Many insoluble carboxylic acids react rapidly with aqueous solutions containing a chemical base and dissolve as the neutralization generates a soluble salt. Carboxylic acids in aqueous solution and liquid or molten carboxylic acids can react with active metals to form gaseous hydrogen and a metal salt. Such reactions occur in principle for solid carboxylic acids as well, but are slow if the solid acid remains dry. Even "insoluble" carboxylic acids may absorb enough water from the air and dissolve sufficiently in 2,5-Dichlorobenzoic acid to corrode or dissolve iron, steel, and aluminum parts and containers. Carboxylic acids, like other acids, react with cyanide salts to generate gaseous hydrogen cyanide. The reaction is slower for dry, solid carboxylic acids. Insoluble carboxylic acids react with solutions of cyanides to cause the release of gaseous hydrogen cyanide. Flammable and/or toxic gases and heat are generated by the reaction of carboxylic acids with diazo compounds, dithiocarbamates, isocyanates, mercaptans, nitrides, and sulfides. Carboxylic acids, especially in aqueous solution, also react with sulfites, nitrites, thiosulfates (to give H2S and SO3), dithionites (SO2), to generate flammable and/or toxic gases and heat. Their reaction with carbonates and bicarbonates generates a harmless gas (carbon dioxide) but still heat. Like other organic compounds, carboxylic acids can be oxidized by strong oxidizing agents and reduced by strong reducing agents. These reactions generate heat. A wide variety of products is possible. Like other acids, carboxylic acids may initiate polymerization reactions; like other acids, they often catalyze (increase the rate of) chemical reactions.
Fire Hazard    Flash point data for 2,5-Dichlorobenzoic acid are not available; however, 2,5-Dichlorobenzoic acid is probably combustible.
Purification Methods    Crystallise the acid from water. [Beilstein 9 IV 1005.] Aromatic acid impurities (to <0.05%) can be removed via the (±)--methylbenzylamine salt as described for 2,4-dichlorobenzoic acid [Ley & Yates Organic Process Research & Development 12 120 2008.]
2,5-Dichlorobenzoic acid Preparation Products And Raw materials
Raw materials    Potassium permanganate-->Paraformaldehyde-->1,2,4-Trichlorobenzene-->p-Dichlorobenzene-->2,5-DICHLOROBENZOYL CHLORIDE-->2,5-Dichlorobenzonitrile-->METHYL 2,5-DICHLOROBENZOATE-->1,4-DICHLORO-2-IODOBENZENE-->2',5'-Dichloroacetophenone-->2,5-DICHLOROTOLUENE
Preparation Products    Irsogladine-->2,3-DICHLOROBENZAMIDE-->2,4,5-Trichlorobenzoic acid