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ChemicalBook CAS DataBase List N-Bromosuccinimide
128-08-5

N-Bromosuccinimide synthesis

3synthesis methods
N-Bromosuccinimide (NBS) is a widely used mild brominating agent and used as chemical intermediate and building block for several chemical production processes, especially in pharma related applications.
Preparation of N-bromosuccinimide
1.62mol (160g) succinimide is dissolved in a mixture of 1.60mol (64g) NaOH, 300g crushed ice and 400ml water. Cool the mixture in an ice bath, and add 85ml (1.65 mol, 264g) Br2 at once while stirring violently. Stir for two more minutes, then filter the precipitated product and wash with ice water. Dry in a desiccator. Yield 75-81%.
Don't clean up NBS too much, the stinky yellow stuff still containing a bit of Br2 works best.
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Yield:128-08-5 96%

Reaction Conditions:

with hydrogenchloride;sodium chlorite;sodium bromide in water at 0 - 25; for 1.5 h;Temperature;

Steps:

2

(1) 1,000 ml of a three-necked flask was used and the temperature was controlled at 25 ° C. 1 mol of succinimide (98.5% purity) and 1.08 mol of sodium bromide were dissolved in 350 ml of water;(2) The temperature was controlled at 20 ° C while stirring, while 1.08 mol of sodium hypochlorite and 10% of 1.09 mol of dilute hydrochloric acid were added dropwise to the flask.(3) the reaction was stirred for 1 hour;(4) stirring down to 0 , holding 0.5 hours, filter, the crude product;(5) The crude product was washed with ice water and dried to obtain N-bromosuccinimide in a yield of 96% (based on succinimide) with a purity of 98.5%

References:

CN106432037,2017,A Location in patent:Paragraph 0011

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