Question

8) An organic compound 'A' having molecular formula C₄ H₈ on treatment with dil H₂ SO₄ gives 'B', 'B' on treatment with conc. HCI and anhydrous ZnCI₂ gives 'C' and on treatment with sodium ethoxide gives back 'A' . Identity the compounds 'A', 'B' and 'C' and write the equation involved.

Answer 1

Dear Student,

Compound A= But-2-ene
Compound B= Butan-2-ol
Compound C= 2-Chlorobutane

The reactions are shown below :

$$\begin{gathered} {\mathrm{CH}}_3\mathrm{CH}={\mathrm{CHCH}}_3+\hspace{0.17em}{\mathrm{H}}_2{\mathrm{SO}}_4\to {\mathrm{CH}}_3\mathrm{CH}\left(\mathrm{OH}\right){\mathrm{CH}}_2{\mathrm{CH}}_3 \\ \left(\mathrm{A}\right)\left(\mathrm{B}\right) \\ {\mathrm{CH}}_3\mathrm{CH}\left(\mathrm{OH}\right){\mathrm{CH}}_2{\mathrm{CH}}_3+\mathrm{HCl}+{\mathrm{ZnCl}}_2\to {\mathrm{CH}}_3\mathrm{CH}\left(\mathrm{Cl}\right){\mathrm{CH}}_2{\mathrm{CH}}_3 \\ \left(\mathrm{B}\right)\left(\mathrm{C}\right) \\ {\mathrm{CH}}_3\mathrm{CH}\left(\mathrm{Cl}\right){\mathrm{CH}}_2{\mathrm{CH}}_3+{\mathrm{CH}}_3{\mathrm{CH}}_2\mathrm{ONa}\to {\mathrm{CH}}_3\mathrm{CH}={\mathrm{CHCH}}_3 \\ \left(\mathrm{C}\right)\left(\mathrm{A}\right) \end{gathered}$$