Chemistry - GOC Question with Solution | TestHub

Site 3 is an aliphatic tertiary amine with an available lone pair. Site 4 is an aniline-type secondary amine whose lone pair is partly delocalized into phenyl. Sites 1 and 2 are amide nitrogens, with strong carbonyl delocalization; the alkyl substitution at secondary-amide ${\mathrm{N}}_1$ makes its lone pair more available than that of primary-amide ${\mathrm{N}}_2$ in this qualitative comparison. Thus 3 > 4 > 1 > 2. Actual amides normally protonate preferentially at oxygen, so this is a nitrogen-lone-pair comparison.