Halogenalkanes Flashcards
What is a haloalkane?
It is an alkane with at least one halogen atom in place of a hydrogen atom
What type of bonds are there in haloalkanes?
There are polar bonds as halogens are more electronegative than carbon
What is a nucleophile?
A lone pair donor
Which are the three nucleophiles that can react with haloalkanes?
OH-
CN-
NH3
What is a nucleophilic substitution reaction?
A reaction where nucleophile reacts with a polar molecule by removing the functional group and taking its place
How does a nucleophilic substitution reaction work?
The lone pairs on the nucleophile attack the delta positive charge on the carbon
The carbon-halogen bond breaks
The halogen leaves taking both electrons
A new bond forms between the carbon and the nucleophile
What is produced when haloalkanes react with hydroxides?
Alcohols
What are the conditions for the reaction of haloalkanes with hydroxides?
Warm
Aqueous
Sodium/Potassium hydroxide
What is produced when haloalkanes react with cyanide?
Nitriles
What are the conditions for the reaction of haloalkanes with cyanide?
Warm
Ethanoic
Potassium cyanide
What is produced when haloalkanes react with ammonia?
Amines
What are the conditions for the reaction of haloalkanes with ammonia?
Excess, concentrated NH3
Ethanoic
At pressure
In a sealed container
Why does the carbon-halogen enthalpy influence the rates of the reaction?
For any reaction to occur, the carbon-halogen needs to break
Which bond has the highest bond enthalpy?
C-F bond
It is the strongest
Therefore, they undergo nucleophilic substitution reactions more slowly
Which bond has the lowest bond enthalpy?
C-I bond
It is easier to break
Therefore, they undergo nucleophilic substitution reactions faster