Question

Benzyl alcohol is obtained from benzaldehyde by

• A. Fittig reaction
• B. Cannizzaro reaction
• C. Kolbe's reaction
• D. Wurtz reciction

Answer 1

Answer: (B)

Benzaldehyde on treatment with $50/$ aqueous or ethanolic alkali solution does not form resin like acetaldehyde but undergoes Cannizzaro's reaction like formaldehyde i.e., one molecule is oxidized and one is reduced with the formation of benzoic acid and benzyl alcohol respectively. This is due to lack of $\alpha$-hydrogen in benzaldehyde
$2C_6{H}_{5}CHO\underset{\text{(50}\%\text{)}}{\overset{\text{KOH}}{\to }}\underset{\text{Benzyl alcohol}}{C_6{H}_{5}C{H}_{2}OH}+\underset{\text{Potassium benzoate}}{C_6{H}_{5}CO\stackrel{-}{O}{K}^{+}}$