Question

An aliphatic unsaturated hydrocarbon (A) when treated with HgSO₄/H₂SO₄ yields a compound (B) having molecular formula C₃H₆O. (B) on oxidation with concentrated HNO₃ gives two compounds (C) and (D). Compound (C), when treated with PCl₅, gives compound (E). (E) when reacts with ethanol gives a sweet-smelling liquid (F). Compound (F) is also formed when (C) reacts with ethanol in the presence of concentrated H₂SO₄.

(i) Identify the compounds A, B, C, D, E and F.
(ii) Give the chemical equation for the reaction of (C) with chlorine in the presence of red phosphorus and name the reaction.

Answer 1

(i)

A - CH3 - C ≡ CH, propyne

B - CH₃COCH₃, Acetone

C – CH₃COOH, Acetic acid

D – HCOOH, Formic acid (or CO₂ + H₂O)

E – CH₃COCl, Acetyl chloride

F – CH₃COOC₂H₅, Ethyl acetate

(ii)

\[\begin{array}{cc}\ce{\underset{\text{Acetic acid}}{CH3COOH} + Cl2->[Red P]{CH2-COOH + HCl}}\\\phantom{.......................}|\\\phantom{........................}\ce{Cl}\\\phantom{.......................}\text{Chloroacetic acid}\end{array}\]

The above reaction is hell - Volhard - Zelinsky.