Question

An organic compound (A) of molecular formula C₂H₆O on reaction with conc.H₂SO₄ at 443 K gives an unsaturated hydrocarbon (B). (B) on reaction with Baeyer’s reagent produces (C) of molecular formula C₂ H₆O₂ . (C) on reaction with anhydrous ZnCI₂ produces (D) of molecular formula C₂H₄O. (D) reduces Tollen’s reagent. Identify A, B, C and D and explain the reactions involved.

Answer 1

1. An organic compound (A) reacts with Conc.H₂SO₄ at 443 K produces ethene by intermolecular dehydration. So, (A) is ethanol – CH₃CH₂OH.

2. Ethene on reaction with Baeyer’s reagent (cold, dilute alkaline KMnO₄) produces ethylene glycol as product (C)

3. Ethylene glycol on reaction with anhydrous ZnCI₂ dehydration and tautomerisation take place to give actaldehyde as product (D).