Match List I with List II : List I (Reaction) List II (Product Characteristics) A. R - CN Na(Hg) / C ₂ H ₅ OH I. Secondary amine with a methyl group B. R - NC LiAlH ₄ II. Primary amine with one carbon less than the substrate C. R - CONH ₂ Br ₂/ aq. NaOH III. Primary amine with the same number of carbon atoms as the substrate D. R - NO ₂ Sn + HCl IV. Primary amine formed by reduction of an oxygen-containing nitrogen c

Step-by-step solution

Reaction A: Reduction of nitriles ( R - CN ) with Na(Hg) / C ₂ H ₅ OH (Mendius reduction) yields a primary amine with the same number of carbon atoms as the starting nitrile. (A matches III) Reaction B: Reduction of isonitriles ( R - NC ) with LiAlH ₄ yields a secondary amine containing a methyl group ( R - NH - CH ₃ ). (B matches I) Reaction C: Hoffmann bromamide degradation of amides ( R - CONH ₂ ) with Br ₂ and aqueous NaOH produces a primary amine with one carbon atom less than the parent amide. (C matches II)