Which reagent is commonly used to reduce nitrobenzene to aniline?

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Multiple Choice

Which reagent is commonly used to reduce nitrobenzene to aniline?

Reducing a nitro group to an amine requires a strong reducing environment that can deliver electrons and protons step by step to convert Ar-NO2 into Ar-NH2. Tin in acidic solution does exactly that in a classic Bechamp-type reduction. The tin metal donates electrons, while the acid provides protons, allowing the nitro group to be reduced through intermediate forms (nitroso and hydroxylamine) all the way to the amine. This combination is widely used because it effectively converts nitrobenzenes to anilines under practical conditions. The other reagents listed aren’t suitable for this transformation. Sodium borohydride is a mild hydride donor that typically reduces aldehydes and ketones but is not strong enough to reduce a nitro group to an amine. PCC is an oxidizing agent used to oxidize alcohols to carbonyls, not to reduce nitro groups. KMnO4 is a strong oxidant, not a reducing agent, so it wouldn’t convert nitrobenzene to aniline.

Reducing a nitro group to an amine requires a strong reducing environment that can deliver electrons and protons step by step to convert Ar-NO2 into Ar-NH2. Tin in acidic solution does exactly that in a classic Bechamp-type reduction. The tin metal donates electrons, while the acid provides protons, allowing the nitro group to be reduced through intermediate forms (nitroso and hydroxylamine) all the way to the amine. This combination is widely used because it effectively converts nitrobenzenes to anilines under practical conditions.

The other reagents listed aren’t suitable for this transformation. Sodium borohydride is a mild hydride donor that typically reduces aldehydes and ketones but is not strong enough to reduce a nitro group to an amine. PCC is an oxidizing agent used to oxidize alcohols to carbonyls, not to reduce nitro groups. KMnO4 is a strong oxidant, not a reducing agent, so it wouldn’t convert nitrobenzene to aniline.

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