Compound A from the following reaction sequence is :

Step-by-step solution

When aniline treated with bromine, the reaction results in the formation of 2 , 4 , 6 -tribromo phenylamine. This reaction is an example of bromination. The process of conversion of a primary aromatic amino compound into a diazonium salt is known as diazotization. This process is carried out by adding an aqueous solution of sodium nitrite to a solution of primary aromatic amine (e.g., aniline) in excess of HCl at a temperature below 5 ° C . Benzene diazonium chloride reacts with H 3 PO 2 in aqueous medium to f