Which of the follwing bases will give the best yield a mixture of alkenes on dehydrohalgenation ?

Options

A. `n`-Butyl bromide
B. sec-Butyl bromide
C. Isobutyl bromide
D. tert-Butyl bromide

Answer

B

Explanation

Unless it is specified, we must consider dehydrohalogenation as `E2` elimination where there is no possibility of rearrangement as carbocation is not formed.
(1) `CH_(3)CH_(2)CH_(2)CH_(2)BrrarrCH_(3)CH_(2)CH=CH_(2)`
(2) `CH_(3)CH(Br)CH_(2)CH_(3)rarrCH_(2)=CHCH_(2)CH_(3)+CH_(3)CH=CHCH_(3)`
(3) `(CH_(3))_(2)CHCH_(2)Brrarr(CH_(3))_(2)C=CH_(2)`
(4) `(CH_(3))_(3)CBrrarr(CH_(3))_(2)C=CH_(2)`