Question

Observe the following reactions \[ \mathrm{Isobutene} \xrightarrow[\mathrm{H^+}]{\mathrm{H_2O}} X \] \[ \mathrm{Isobutane} \xrightarrow{\mathrm{KMnO_4}} Y \] The correct statement regarding \(X\) and \(Y\) is

• A. Both \(X\) and \(Y\) are primary alcohols
• B. Both \(X\) and \(Y\) are tertiary alcohols
• C. \(X\) is primary alcohol and \(Y\) is carboxylic acid
• D. \(X\) is tertiary alcohol and \(Y\) is carboxylic acid

Hint:

Isobutene undergoes Markovnikov hydration to form tert-butyl alcohol. Isobutane on oxidation with hot alkaline \(\mathrm{KMnO_4}\) gives tert-butyl alcohol.

Answer 1

The Correct Option is B

Step 1: Identify product \(X\). Acid-catalysed hydration of isobutene follows Markovnikov's rule. \[ \mathrm{CH_2=C(CH_3)_2} \xrightarrow[\mathrm{H^+}]{\mathrm{H_2O}} \mathrm{(CH_3)_3COH} \] Thus, \[ \boxed{X=\text{tert-butyl alcohol (tertiary alcohol)}}. \]

Step 2: Identify product \(Y\). Oxidation of isobutane with hot alkaline \(\mathrm{KMnO_4}\) occurs at the tertiary hydrogen atom to form \[ \mathrm{(CH_3)_3COH}. \] Hence, \[ \boxed{Y=\text{tert-butyl alcohol (tertiary alcohol)}}. \] Therefore, \[ \boxed{\text{Both }X\text{ and }Y\text{ are tertiary alcohols}.} \] Hence, \[ \boxed{(B)} \] is the correct answer.