What reagent is used to convert an amide into a primary amine with one fewer carbon atom (Hofmann Bromamide Degradation)? (Hard)
Answer and explanation
Correct answer: D. Bromine (Br2) and aqueous or alcoholic Potassium Hydroxide (KOH)
- Step 1: Hofmann degradation treats primary amide (R-CONH2) with Br2 and alkali (KOH/NaOH). Step 2. Through nitrene and isocyanate intermediates, carbon dioxide is lost, producing a primary amine R-NH2 with one carbon fewer than the starting amide. Answer: Bromine (Br2) and aqueous or alcoholic Potassium Hydroxide (KOH). Why not the others: LiAlH4 reduces amides to amines with the same number of carbons; PCl5 dehydrates amides to nitriles; nitric acid oxidizes amides.
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