Question

Answer the following questions:
What happens when:
(i) Propene is treated with HBr
(ii) Benzene is treated with CH₃Cl in ppresence of anhydrous AlCl₃
(iii) CHCl₃ is treated with Ag powder and heat.

Answer 1

Dear Student,

(i) Addition reaction takes place when HBr is added to propene. Br gets attached on the carbon which has lesser number of H atom i.e. more substituted carbon, which is in accordance with Markovnikov rule. Hence, 2-bromopropane will be formed.
​${\mathrm{CH}}_3-\mathrm{CH}={\mathrm{CH}}_2+\mathrm{HBr}\to {\mathrm{CH}}_3-\mathrm{CH}\left(\mathrm{Br}\right)-{\mathrm{CH}}_3$

(ii)Friedel Crafts's alkyaltion will occur to produce toluene as the product.
${\mathrm{C}}_6{\mathrm{H}}_6+{\mathrm{CH}}_3\mathrm{Cl}\stackrel{\mathrm{Anhy}.{\mathrm{AlCl}}_3}{\to }{\mathrm{C}}_6{\mathrm{H}}_5{\mathrm{CH}}_3$

(iii) Acetylene will be formed as product.
$2{\mathrm{CHCl}}_3+\hspace{0.17em}6\mathrm{Ag}\to \mathrm{CH}\equiv \mathrm{CH}+6\mathrm{AgCl}$