An unknown solid melting at 140 - 142 degree was subjected to sodium fusion and

Question

An unknown solid melting at 140 - 142 degree was subjected to sodium fusion and then tested for N, known S and X. The stock solution tested positive for nitrogen and halogen. The liquid did not dissolve in dilute NaHCO_3, NaOH, or HCI but did dissolve in either and conc. H_2 sO_4. Treatment with NH_2 OH followed by a FeCI_3 solution gave a purple solution. When refluxed with water and NaOH, two components were isolated, A and B. A was soluble in both dilute NaHCO_3 and NaOH and melted at 150-151 degree after recrystallization and contained halogen. A had a neutralization equivalent of 157 plusminus 2. Treatment of A with thionyl chloride followed by ammonia gave a solid derivative which melted at 153-1540. B (bp 181-183 degree) was found to be soluble in dilute HCI and ether and contained nitrogen. The component B gave negative 2.4 DNP but gave a precipitate when bromine water was added. Reaction with benzenesulfonyl chloride and NaOH gave a clear homogeneous solution. Acidification of this solution gave a white solid which melted at 111 -112 degree after recrystallization. Identify the original unknown compound and compounds A and B. Show equations for all reactions.

Explanation / Answer

Unknown solid was soluble in ether and H2SO4, so it is possibly an ester

Ester hydrolyzed with NaOH, H2O to form an carboxylic acid (A) and alcohol (B)

A has halogen, reacts with SOCl2 and NH3 to form an amide, so it may be an aliphatic/aromatic halogen containing carboxylic acid compound

B has nitrogen and is phenolic is nature

Possible structure for A,

Br-CH2CH2COOH

Possible structure for B,

NH2-C6H4OH

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