1-хлор-2-нитробензол

Химические свойства

yellow solid with a characteristic odour

Использование

Intermediate, especially for dyes.

Методы производства

Nitration of chlorobenzene with mixed acid (30/56/14) typically gives an isomer mix in 98 % yield consisting of 34 – 36 % 2-Nitrochlorobenzene, 63 – 65 % 4- chloronitrobenzene, and only ca. 1 % 3- chloronitrobenzene. The ortho – para ratio of about 0.55 is in sharp contrast to the 1.6 obtained with nitrotoluene isomers. As with the nitration of toluene, much work has been done on isomer control so that the producer might have some flexibility towards the balance of isomer demand. Although no major change in ratio has been achieved, the situation is better for nitrochlorobenzene than nitrotoluenes, because the favored isomer is in much greater demand. In further contrast to the nitration of toluene, the nitration of chlorobenzene in the presence of phosphoric acid decreases the proportion of 4-Nitrochlorobenzene, and the use of phosphoric acid in the presence of a transition-metal catalyst is said to increase the ortho – para ratio to ca. 0.8.

Общее описание

Yellow crystals with an aromatic odor. Sinks in water.

Реакции воздуха и воды

2-Nitrochlorobenzene may be sensitive to prolonged exposure to air and light. Insoluble in water.

Профиль реактивности

O-NITROCHLOROBENZENE is incompatible with strong bases and strong oxidizing agents. 2-Nitrochlorobenzene will react with ammonia.

Опасность

Toxic by inhalation and ingestion. Combustible. Questionable carcinogen.

Угроза здоровью

INHALATION: Headache, languour, anemia. Irritation of nose and throat, cyanosis, shallow respiration, convulsions, and coma. EYES: Irritation. SKIN: Irritation. INGESTION: Forms methemoglobin giving rise to cyanosis and blood changes.

Профиль безопасности

Suspected carcinogen with experimental carcinogenic and neoplastigenic data. Poison by ingestion, skin contact, and probably inhalation. Combustible when exposed to heat or flame. To fight fire, use water, foam. Potentially explosive reaction with ammonia at 160℃/30 bar. When heated to decomposition it emits toxic fumes of Cl-, NOx, and phosgene. See also other chloronitrobenzene entries and NITRO COMPOUNDS of AROMATIC HYDROCARBONS.

Методы очистки

Crystallise it from EtOH, MeOH or pentane (charcoal). [Beilstein 5 IV 721.]