2-Nitropropane is reduced by passing hydrogen gas in the presence of…

The correct answer is Option (4) → Propan-2-amine

Nitro compounds are reduced to amines by hydrogen with finely divided nickel, palladium or platinum, and nitroalkanes give the corresponding alkanamines. The –NO₂ group becomes –NH₂ on the same carbon; the carbon chain is not changed.

    \( \displaystyle \ce{CH3CH(NO2)CH3 + 3H2} \xrightarrow{\ce{Ni}} \ce{CH3CH(NH2)CH3 + 2H2O} \)

Why the other options are incorrect

Option (1) Propan-1-amine — Incorrect. Its –NH₂ group is on carbon 1; it would come from 1-nitropropane. The nitrogen does not move during the reduction.

Option (2) N-Methylethanamine — Incorrect. This is a secondary amine with nitrogen between two carbon groups. Reduction of a nitro group gives a primary amine, –NH₂.

Option (3) Propan-2-ol — Incorrect. Reduction keeps the C–N bond and gives an amine, not an alcohol. An alcohol forms when a primary aliphatic amine reacts with nitrous acid.

NCERT (2026-27 edition):
9.4 Preparation of Amines – “1. Reduction of nitro compounds: Nitro compounds are reduced to amines by passing hydrogen gas in the presence of finely divided nickel, palladium or platinum and also by reduction with metals in acidic medium. Nitroalkanes can also be similarly reduced to the corresponding alkanamines.”