Esterifications
Esterifications
Fischer Esterification
The Fischer Esterification is the acid catalyzed reaction of an alcohol and a carboxylic acid to form an ester.
In order to drive the equilibrium of the Fischer Esterification to the ester product side, two things are commonly done. One trick is to run the reaction with an excess of starting materials. A large excess of either the alcohol or the carboxylic acid will work. The other trick is to remove the water product from the reaction using a dehydrating agent in the reaction flask that can absorb water, like molecular sieves. Also, water can be removed from a reaction using a Dean-Stark trap. This is a special attachment to a reflux apparatus that helps remove water from a reaction.
From an acid chloride
Another effective way to make an ester is to react an alcohol with an acid chloride. This is an exothermic reaction that is not an equilibrium reaction. The reaction usually proceeds well. Sometimes a base is put into the reaction flask to soak up the HCl that is produced. Acid chlorides can be made from reacting carboxylic acids with SOCl2.
One drawback for this reaction is that it is more water sensitive than a Fischer Esterification. Water will quench the acid chloride and turn it into a carboxylic acid.
9. Draw the reactant or products in the following reactions, as appropriate.
a)
b)
c)
d)
e)
f)
g)
Answers
9. Draw the reactant or products in the following reactions, as appropriate.
a)
b)
c)
d)
e)
f)
g)
