Hydrogen Bromide → 1-Bromo-2,3-dichlorobenzene

Participants

Reaction Conditions

Reaction Steps

163 g 2,3-Dichloroaniline (1.0 mol) is added to a mixture of 3250 g of 30% aqueous HBr (12.0 mole) and 25.4 g copper powder of a particle size of approx. 45μ at 35-37° C. The mixture is stirred for 15 minutes at 35-37° C. Then, 766 g of an aqueous solution of NaNO2 (40% solution in water, 4.44 mole) is added via subsurface feeding over a period of 3 hours at 35° C. Parallel to the addition of the sodium nitrite 489 g 2,3-dichloroaniline (3.0 mol) is added over a period of 2.5 hours at the same temperature. The addition of dichloraniline starts 15 minutes after the start of the addition of sodium nitrite. After all additions are complete the reaction mixture is stirred for 30 minutes at 35° C. Then, the reaction mixture is heated to 60-65° C. The organic phase containing the reaction product is separated from the aqueous phase. The remaining liquid is discarded and the crude product is washed twice with 200 ml water. 792.2 g of crude solid 1-bromo-2,3-dichlorobenzene is obtained (87.7% of theory) with a purity of 86.2%).

Provenance & Evidence