What reaction occurs when benzaldehyde is heated with concentrated sodium hydroxide in the absence of alpha-hydrogens?
Answer and explanation
Correct answer: B. Cannizzaro reaction
Aldehydes lacking alpha-hydrogens (such as benzaldehyde or formaldehyde) cannot form enolates. In strong base, they undergo the Cannizzaro redox disproportionation: one molecule is reduced to benzyl alcohol while another is oxidized to sodium benzoate.
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