JEE PYQ: Haloalkanes And Haloarenes Question 11
Question 11 - 2020 (08 Jan Shift 1)
The decreasing order of reactivity towards dehydrohalogenation ($\text{E}_1$) reaction of the following compounds is:
(A) $\text{Cl}-\text{CH}_2\text{CH}_2\text{CH}_2\text{CH}_2\text{CH}_3$ (primary) (B) $\text{Cl}-\text{CH}_2\text{CH}(\text{CH}_3)\text{CH}_2\text{CH}_3$ (secondary-like) (C) Chlorocyclohexane (D) Allyl chloride with Cl on cyclohexene ring
(1) D > B > C > A
(2) B > D > A > C
(3) B > D > C > A
(4) B > A > D > C
Show Answer
Answer: (3)
Solution
$\text{E}_1$ reaction proceeds via carbocation formation, therefore greater the stability of carbocation, faster will be the $\text{E}_1$ reaction. Thus correct decreasing order of the given halides towards dehydrohalogenation by $\text{E}_1$ is D > B > C > A.
BETA
