ChemicalBook CAS DataBase List 2-Nitrobenzyl bromide

2-Nitrobenzyl bromide synthesis

6synthesis methods

Product Name:2-Nitrobenzyl bromide
CAS Number:3958-60-9
Molecular formula:C7H6BrNO2
Molecular Weight:216.03

88-72-2

3958-60-9

In a 5000 L bromination reactor, 300 kg of dichloroethane, 226 kg of o-nitrotoluene and 27 kg of azobisisobutyronitrile were added sequentially. After stirring for 20 minutes, the mixed solution was transferred to a high tank and set aside; the bromination reactor was then refilled. To the reactor, 300 kg of dichloroethane and 226 kg of o-nitrotoluene were added, mixed thoroughly, then 889.03 kg of 40% hydrobromic acid was added, and the mixture was stirred at 72 to 75°C. The mixture was then transferred to the high tank and set aside for 20 minutes. From the high tank, the mixed solution was slowly added to the bromination reactor with 448.26 kg of 30% hydrogen peroxide at a 1:4 dropwise rate. After dropwise addition, the reaction was continued for 2 hours. After completion of the reaction, it was cooled to room temperature and analyzed by HPLC. The feedstock conversion was over 99.0% and no by-products such as dibrominated products were detected. The molar ratio of o-nitrotoluene, 40% hydrobromic acid and 30% hydrogen peroxide in the reaction was 1:1.2:1.2. After static partitioning, the upper aqueous phase was separated; the lower organic phase was washed with 600 L of water, and the solvent was removed by distillation under reduced pressure, and finally washed with cold dichloroethane to obtain a white 2-nitrobenzyl bromide solid product in 98.5% yield.

88-72-2
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$15.00/25g

3958-60-9
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$8.00/1g

Yield:3958-60-9 98.5%

Reaction Conditions:

Stage #1:1-methyl-2-nitrobenzene with 2,2'-azobis(isobutyronitrile) in 1,2-dichloro-ethane for 0.333333 h;
Stage #2: with hydrogen bromide;dihydrogen peroxide in 1,2-dichloro-ethane at 72 - 75; for 2 h;Solvent;Temperature;

Steps:

2
In a 5000-L bromination reactor, 300 kg of dichloroethane, 226 kg of o-nitrotoluene, and 27 kg of azobisisobutyronitrile are successively added. After stirring for 20 minutes, the solution is pumped into a high tank for use; and the bromination reactor is put in again. 300 kg of dichloroethane and 226 kg of o-nitrotoluene were mixed well, and 889.03 kg of 40% hydrobromic acid was added, and the mixture was stirred at a temperature of 72 to 75°C. In the upper slot The mixed solution and 448.26 kg of 30% hydrogen peroxide were slowly added dropwise to the bromination reactor at an acceleration of 1:4. At the end of the addition, the reaction was continued for 2 hours. After the reaction was completed, the temperature was lowered to room temperature, and the reaction liquid was subjected to HPLC analysis. The conversion of the raw material was greater than 99.0%, and no by-product such as dibrominated product was generated. The molar ratio of raw material, 40% hydrobromic acid and 30% hydrogen peroxide in the reaction is 1: 1.2:1.2. The solution was allowed to stand for delamination and the upper aqueous layer was separated; after the lower organic phase was washed with 600 L of water, the solvent was distilled off under reduced pressure and rinsed with cold dichloroethane to obtain white o-nitrobenzyl bromide solid product. It is 98.5%.

References:

Zhejiang Zhongshan Chemical Group Co., Ltd.;Li Jing;Wang Tao;Chen Lu;Yu Ronghua CN107778181, 2018, A Location in patent:Paragraph 0008; 0028; 0029

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612-25-9 Synthesis