SURAT CHEMICAL TAG::
NBS is used as a substitute for Br2 in these cases since Br2 tends to react with double bonds to form dibromides. The advantage of NBS is that it provides a low-level concentration of Br2, and bromination of the double bond doesn't compete as much.
N-Bromosuccinimide (NBS) is a brominating and oxidizing agent that is used as source for bromine in radical reactions (for example: allylic brominations) and various electrophilic additions.
N-Bromosuccinimide or NBS is a chemical reagent used in radical substitution, electrophilic addition, and electrophilic substitution reactions in organic chemistry.