N-Bromo Succinimide (NBS)

AD PHARMACHEM is known for manufacturer of N-Bromo Succinimide (NBS) intermediates.

N-Bromo Succinimide (NBS) is a versatile chemical reagent widely used in organic chemistry, particularly for bromination reactions.

 

N-Bromo succinimide (NBS) appears as a crystalline powder, ranging in color from white to slightly yellow. 

 

N-Bromo succinimide (NBS) is commercially available, but it can also be synthesized in the laboratory. N-Bromo succinimide (NBS) is synthesized by combining succinimide, sodium hydroxide, and bromine in an ice-water solution. Through filtration, the precipitated NBS product can be gathered.

 

Crude NBS tends to give a better yield in the Wohl–Ziegler reaction. However, in other applications, impure NBS (which appears slightly yellow) may produce unreliable results. To purify NBS, it can be recrystallized from water at a temperature of 90 to 95 °C, using 10 grams of NBS for every 100 mL of water.

N-Bromo Succinimide Physical and Chemical Properties:

1. Appearance : Crystalline powder, white to slightly yellow in color. 

2. Melting Range : 176°C – 182°C. 

 

3. Loss on Drying (LOD) : Not more than 0.1% when dried at 60°C for 3 hours.

 

4. Solubility : Sparingly Soluble in: Methanol, Soluble in: Acetone, Acetic Acid, Sodium Hydroxide.

 

 

5. Identification : By IR Spectroscopy: The infrared absorption spectrum of the substance being examined must be concordant with the IR spectrum obtained from a working standard.

 

6. Assay : By Titration: NBS must contain not less than 98.0% of the active substance.

N-Bromo Succinimide

Application of N-Bromo Succinimide

NBS is primarily used in organic synthesis for selective bromination of alkenes, alkynes, and aromatic compounds. Its specific applications include:

1. Bromination of Alkenes: NBS is widely used to brominate alkenes at the allylic position. The reaction typically involves radical intermediates and is initiated by light or a radical initiator.

 

Example: 

R-CH=CH₂ + NBS→R-CH=CHBr

 

2. Bromination of Aromatic Compounds: NBS can brominate aromatic rings, usually at the position para to an electron-donating group.

 

Example: 

Ph-OH + NBS→Ph-OH(p-Br) 

 

3. Oxidation Reactions: NBS can act as an oxidizing agent in various organic transformations, such as the conversion of alcohols to carbonyl compounds. 

 

Example: 

R-CH₂OH + NBS→R-CHO  

 

4. Halolactonization: NBS is used in the halolactonization of alkenoic acids, where a halogen and a lactone are introduced in the same molecule.