Hydrogen Bromide → 2-Bromo-3-nitrotoluene

Beteiligte Stoffe

Reaktionsschritte

A stirred solution of 2-methyl-6-nitroaniline (75.0 g, 0.493 mole) and 40 ml of hydrobromic acid (48% solution) in 135 ml of water was cooled to 0°. During a one hour period a solution of sodium nitrite (36.2 g, 0.51 mole) in 60 ml of water was added to the reaction mixture. The mixture was suction filtered through a sintered glass funnel, collecting the filtrate in a flask cooled by a dry ice-acetone bath. The filtrate was placed in a jacketed addition funnel cooled by a dry ice-acetone bath. During a five minute period this solution was added to a stirred mixture of cuprous bromide (77.8 g, 0.51 mole) in 165 ml of hydrobromic acid (48% solution). After complete addition, the mixture was stirred at room temperature for approximately 18 hours, heated at reflux for two hours, then steam distilled. The distillate was extracted with methylene chloride and the extract washed with 2N aqueous sodium hydroxide, followed by several portions of saturated aqueous sodium chloride solution. The organic phase was passed through phase separation filter paper and evaporated under reduced pressure to give 1-bromo-2-methyl-6-nitrobenzene (17 g) as a solid.

Herkunft & Nachweise