Write the structures and $IUPAC$ names of:
$(i)$ the amide which gives propanamine by Hoffmann bromamide reaction
$(ii)$ the amine produced by the Hoffmann degradation of benzamide.

(N/A) $(i)$ Propanamine contains three carbon atoms. Hoffmann bromamide degradation reaction involves the loss of one carbon atom from the amide group. Hence,the starting amide must contain four carbon atoms. The structure and $IUPAC$ name of the amide are:
$CH_3-CH_2-CH_2-CONH_2$ (Butanamide)
$(ii)$ Benzamide is an aromatic amide containing seven carbon atoms. Hoffmann degradation of benzamide removes the carbonyl carbon,resulting in an aromatic primary amine containing six carbon atoms $(C_6H_5NH_2)$. The product is aniline,also known as benzenamine.