Question

The reaction: ${\left({\left(CH\right)}_3\right)}_{3}C-Br\stackrel{H_{2}O}{\to }{\left({\left(CH\right)}_3\right)}_{3}C-OH$ is a/an

• A. elimination reaction
• B. substitution reaction
• C. free radical reaction
• D. none of these

Answer 1

Answer: (B)

In this reaction, first of all, the formation of a carbocation occurs by the removal of bromide ion. Then, $H_{2}O$ molecule attacks the carbocation, and an intermediate (protonated alcohol) is formed. This oxonium ion undergoes deprotonation with the help of a water molecule to give rise to an alcohol and a hydronium ion.
This is an example of a nucleophilic substitution reaction. As the substitution occurs by forming a tertiary carbocation, it is a type of unimolecular nucleophilic substitution reaction $(S_{N}1)$ .