JEE PYQ: Haloalkanes And Haloarenes Question 24
Question 24 - 2019 (10 Jan Shift 1)
Which hydrogen in compound (E) is easily replaceable during bromination reaction in presence of light?
$\text{CH}_3 - \overset{\delta}{\text{CH}_2} - \overset{\beta}{\text{CH}} = \overset{\alpha}{\text{CH}_2}$
(1) $\alpha$-hydrogen
(2) $\gamma$-hydrogen
(3) $\delta$-hydrogen
(4) $\beta$-hydrogen
Show Answer
Answer: (2)
Solution
Allylic H is replaced due to the greater stability of allylic free radical. $\text{CH}_3-\text{CH}_2-\text{CH}=\text{CH}_2 + \text{Br}_2 \xrightarrow{h\nu} \text{CH}_3-\text{CH}(\text{Br})-\text{CH}=\text{CH}_2$.
BETA
