2-Bromo-1,4-dichlorobenzene

Chemical Properties

Uses

Synthesis

106-46-7

1435-50-3

4571-24-8

General procedure for the synthesis of 1-bromo-2,5-dichlorobenzene and 1,4-dibromo-2,5-dichlorobenzene from 1,4-dichlorobenzene: 147.0 g (1.00 mol) of 1,4-dichlorobenzene was accurately weighed in a reactor, and 515 g of carbon tetrachloride was added as a solvent to make it completely soluble. Subsequently, 7.35 g of anhydrous aluminum chloride was added to the solution as a catalyst and after stirring for 15 minutes, the temperature of the reaction system was raised to 35°C. At this temperature, dropwise addition of 105.6 g (0.66 mol) of bromine was initiated at a constant dropwise acceleration, and the dropwise process lasted for 9 hours to complete. Upon completion of the reaction, 200.0 g of 5% mass fraction sodium bisulfite solution was added to the reaction mixture until the color of the mixture changed to colorless. After standing and layering, the organic phase was separated and the resulting carbon tetrachloride layer was concentrated. Eventually, 73.0 g (0.50 mol) of unreacted 1,4-dichlorobenzene, 111.5 g (0.48 mol) of 1-bromo-2,5-dichlorobenzene and 7.1 g (0.02 mol) of 1,4-dibromo-2,5-dichlorobenzene were obtained by distillation.

References