Organic+-+Substitution+reactions

=Substitution Reactions=

A substitution reaction is one in which an atom or functional group attached to a carbon in an organic compound is/are replaced by a different atom or functional group. i.e: AB + CD ---> AC + BD

This is the only way that a halogen can be added to an alkane: Here you can see that the chlorine is replacing a hydrogen in the methane to form methyl chloride.

In a reaction such as butane with chlorine, there are two things that can happen. The result will hydrochloric acid along with either be 1-chlorobutane or 2-chlorobutane depending on which carbon the chlorine attaches to:



Substitution reactions can also occur with benzene: //Benzene + Chlorine -> Chlorobenzene//

__Another Example__: Ethane + Bromine ---> Bromoethane + Hydrogen Bromide CH3CH3 + Br2 > CH3CH2Br + HBr

UV in sunlight is a catalyst for the reaction. The Hydrogen Bromide will turn moist blue litmus paper red. Bromoethane can still react further, as the other H atoms can still be replaced - Dibromoethane, Tribromoethane and Tetrabromoethane can also be produced. Chlorine will react with alkanes similarly (as in the other examples above).

Sources: [] [] []