Question

Arrange the following alcohols in increasing order of their reactivity towards the reaction with $HCl$.
$\left( CH _{3}\right)_{2} CH - OH (1),\left( CH _{3}\right)_{3} C - OH (2),\left( C _{6} H _{5}\right)_{3} COH (3)$

• A. 1 < 2 < 3
• B. 2 < 1 < 3
• C. 3 < 1 < 2
• D. 2 < 3 < 1

Answer 1

Answer: (A)

Alkylhalide formation in the reaction of alcohol with $HCl$ undergoes $S_N1$ reaction in which formation of the carbocation as intermediate occurs. Stability of carbocation is greatest for $(C_6H_5)_3C^{+}$ due to resonance effect, and stability of tertiary carbocation is greater than the secondary carbocation