The Total solution for NCERT class 6-12
An aromatic compound ‘A’ on treatment with aqueous ammoniaand heating forms compound
‘B’ which on heating with Br_2 and KOH forms a compound ‘C’ of molecular formula C_6H_7N. Write the structures and IUPAC names of compounds A, B and C.
It is given that compound ‘C’ having themolecular formula, C6H7N is formed by heating compound ‘B’ with Br2 andKOH. This is a Hoffmann bromamide degradation reaction. Therefore, compound ‘B’is an amide and compound ‘C’ is an amine. The only amine having the molecularformula, C6H7N is aniline, (C6H5NH2).
Therefore, compound ‘B’ (from which ’C’ isformed) must be benzamide, (C6H5CONH2).
Further, benzamide is formed by heating compound ‘A’ withaqueous ammonia. Therefore, compound ‘A’ must be benzoic acid.
The given reactions can be explained with the help of thefollowing equations: