Synonyms: azabenzene, azine
Chemical formula: C5H5N
International name: PYRIDINE
CAS No: 110-86-1
Appearance: Colorless liquid
Packing: drums, 200 kg
Storage: Store in a dry, well-ventilated area
PYRIDINE - a colorless liquid with a characteristic odor; miscible in all respects with water and most organic solvents; with water forms an azeotrope.
Pyridine - heterocyclic compound, a weak base; forms salts with acids and N-alkylpyridinium salts C5H5N • RX with alkyl halides (RX), as well as complex compounds with FeCI2, SO2, SO3, Br2, H2O. Pyridin-toxic, the maximum concentration of vapor in air 0.0015 mg / l.
The main source of pyridine - coal tar, in which it contains about 0.08%. Pyridine was prepared:
• from coal tar;
• pyrolysis products from wood, peat, or bones;
• by reacting butadiene with hydrogen cyanide in the presence of aluminum oxide Al2O3:
CH2 = CHCH = CH2 + HCN -> C5H5N
• by reacting acetylene with hydrogen cyanide. The process is catalyzed by mercuric chloride (II):
2HCCH + HCN -> C5H5N
• by thermal cyclocondensation reaction of acetaldehyde, formaldehyde and ammonia at 200-250 ° C at high pressure zeolite catalyst (Chichibabin reaction):
2CH3CHO + CH2O + NH3 -> C5H5N
Pyridine is widely used in organic synthesis industry
• as solvent and reagent in synthetic organic chemistry, and industry;
• as a starting compound and intermediate in the manufacture of insecticides, herbicides, fungicides, dyes, additives to rubbers, adhesives, explosives, disinfectants;
• in the synthesis of pharmaceuticals, food flavoring agents;
• as a denaturant for ethyl technical, antifreeze;
• as an adjuvant in the process of dyeing fabrics, etc.
Pyridine derivatives, such as 2-methyl-5-vinylpyridine, vinylpyridine used in the manufacture of rubbers. Piridinsulfotrioksid C5H5N • SO3 - mild sulfonating agent.