IUPAC name of Acetanilide is

The correct answer is Option (2) → N-Phenylethanamide

Acetanilide is formed when aniline is acetylated: the acetyl group (\( \ce{CH3CO} \)–) replaces one hydrogen of the –\( \ce{NH2} \) group:

    \( \displaystyle \ce{C6H5NH2 + (CH3CO)2O -> C6H5NHCOCH3 + CH3COOH} \)

An amide is named after its parent acid: \( \ce{CH3CONH2} \) is ethanamide. A group attached to the nitrogen of the amide is shown by the prefix N-. In acetanilide, \( \ce{CH3CO-NH-C6H5} \), a phenyl group is on the nitrogen of ethanamide, so its IUPAC name is N-phenylethanamide.