The carbon atoms at which bromination will take place are:

Options

A. 1, 2 and 3
B. 4 and 5
C. I, 3, 4 and 5
D. 1, 3 and 4

Answer

D

Explanation

N-Bromosuccinimide (NBS) is frequently used to brominateallylic positions because it allows a radical substitution reaction to be carried out without subjectingthe reactant to a relatively high concentration of Br, that could add to its double bond.
Carbon atoms at positions 1, 3 and 4 are allylic carbons. The carbon atom at position 5 is not allylic since it becomes acidic due to presence.of carbonyl carbon at the alpha position.