Advices For Studying Organic Chemistry

10.6 HALOGENATION OF HIGHER ALKANES

1. Ethane reacts with chlorine to produce chloroethane:

A Mechanism for the Reaction

Radical Chlorination of Ethane
Reaction:
CH 3 CH 3 + Cl 2 heat
or light

CH 3 CH 2 Cl + HCl

Mechanism:
Chain Initiation

Cl Cl or lightheat Cl + Cl

Chain Propagation

Step 2 CH^3 CH^2 H + Cl CH^3 CH^2 + Cl H

Step 3

CH 3 CH 2 + Cl Cl CH 3 CH 2 Cl + Cl

Chain propagation continues with Step 2, 3, 2, 3, an so on.

Chain Termination

CH 3 CH 2 + Cl CH 3 CH 2 Cl

CH 3 CH 2 + CH 2 CH 3 CH 3 CH 2 CH 2 CH (^3)
Cl + Cl Cl Cl
(^)

2. Chlorination of most alkanes whose molecules contain more than two carbon
   atoms gives a mixture of isomeric monochloro products (as well as more highly
   chlorinated compounds).