An aromatic compound [A] gives a buff-coloured precipitate on treatment with neutral solution…
Chemistry20262 marksIdentify
An aromatic compound [A] gives a buff-coloured precipitate on treatment with neutral $\text{FeCl}_3$ solution. Compound [A] reacts with thionyl chloride to give compound [B], which on reacting with ammonia followed by heating gives compound [C]. Compound [C] on treatment with bromine in KOH forms [D] with molecular formula $\text{C}_6\text{H}_7\text{N}$ and has a characteristic odour. Identify the compounds [A], [B], [C] and [D].
Answer
Answer
Official answer key
A - benzoic acid: C6H5COOH
B - benzoyl chloride: C6H5COCl
C - benzamide: C6H5CONH2
D - aniline: C6H5NH2
A = benzoic acid ($\mathrm{C_6H_5COOH}$)
B = benzoyl chloride ($\mathrm{C_6H_5COCl}$)
C = benzamide ($\mathrm{C_6H_5CONH_2}$)
D = aniline ($\mathrm{C_6H_5NH_2}$)
A gives a buff-coloured precipitate with neutral $\mathrm{FeCl_3}$ (carboxylic acid); B is the acid chloride; C is the amide; Hofmann bromamide degradation of C gives aniline, $\mathrm{C_6H_7N}$.