question_answer

Among the choices of alkyl bromide, the least reactive bromide in \[{{S}_{N}}2\] reaction is

A) 1-bromopentane

B) 2-bromo-2-methylbutane

C) 1-bromo-3-methylbutane

D) 1-bromo-2-methylbutane.

Correct Answer: B

Solution :

The reactivity of different alky! halides towards reaction decreases in the order: methyl halides \[>\text{ }1{}^\circ \] halides \[>\text{ }2{}^\circ \] halides \[>\text{ 3}{}^\circ \] halides.