Identify compounds A and E in the following reaction sequence.

Step-by-step solution

The starting compound is 1-ethyl-4-nitrobenzene. Reaction with Br ₂/ AlBr ₃ is an electrophilic aromatic substitution. The - C ₂ H ₅ group is activating and ortho/para-directing, while the - NO ₂ group is deactivating and meta-directing. Both groups direct the incoming electrophile ( Br ^+ ) to the position ortho to the - C ₂ H ₅ group. Thus, compound A is 2-bromo-1-ethyl-4-nitrobenzene. Reaction with Sn / HCl reduces the - NO ₂ group to an - NH ₂ group, forming compound B (4-amino-2-bromo-1-ethylbenzene). Reaction