Question

How do you convert:
(i) Chlorobenzene to biphenyl
(ii) Propene to 1-iodopropane
(iii) 2-bromobutane to but-2-ene

Answer 1

(i) Chlorobenzene is converted to biphenyl by using Fittig reaction. Chlorobenzene reacts with sodium in presence of ether to form biphenyl.
(ii) Propene to 1-iodopropane.
The hydroboration-oxidation of propene gives 1-propanol.
1-propanol then reacts with $HI$ (obtained from $KI$ + $H_{2}S{O}_4$) to form 1-iodopropane.
(iii) 2-bromobutane to but-2-ene.
The dehydrohalogenation of 2-bromobutane in presence of alcoholic $KOH$ gives but-2-ene as major product.