An aromatic compound ‘A’ on treatment with aqueous ammonia and heating forms compound ‘B’ which on heating with Br2 and KOH forms a compound ‘C’ of molecular formula C6H7N. Write the structures and IUPAC names of compounds A, B and C.

It is given that compound 'C' having the molecular formula,C6H7N is formed by heating compound 'B' with Br2and KOH. This is a Hoffmann bromamide degradation reaction(in which isicyanide compound is formed). Therefore, compound 'B' is an amide and compound 'C' is an amine. The only amine having the molecular formula,C6H7N is aniline, .

Therefore, compound 'B' (from which 'C' is formed) must be benzamide, .


Further, benzamide is formed by heating compound 'A' with aqueous ammonia. Therefore, compound 'A' must be benzoic acid.The given reactions can be explained with the help of the following equations:



Benzoic acid



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