Video Transcript
Fill in the blanks. The hydrolysis of esters using
sodium hydroxide produces blank and alcohols, while the ammonolysis of esters
produces blank and alcohols.
An ester is a compound that
contains a carbonyl group bonded to an alkoxy group. Esters undergo a variety of
reactions. One such reaction is hydrolysis, a
chemical reaction where water reacts with a compound breaking one or more bonds. Ester hydrolysis may be
acid-catalyzed or base-induced. In this question, we are told that
the hydrolysis of esters uses sodium hydroxide, which has the chemical formula
NaOH. Sodium hydroxide is a strong
base. So, let’s examine a base-induced
ester hydrolysis reaction.
Hydrolysis is a reaction where
water reacts with a compound, but water does not appear as a reactant in a
base-induced hydrolysis reaction. This is because in base-induced
ester hydrolysis, it is actually the hydroxy group of the base that reacts with the
ester rather than water. The bond that is broken during this
reaction is the carbon-oxygen single bond of the ester. The alkoxy group of the ester
becomes an alcohol, and the carbonyl group of the ester becomes part of an ionic
compound that contains a carboxylate anion and a metal cation. Since sodium hydroxide was used in
this reaction, this compound is a sodium carboxylate.
The other reaction mentioned in the
question is ammonolysis. Ammonolysis is a chemical reaction
where ammonia reacts with a compound, breaking one or more bonds. When ammonia reacts with an ester,
the carbon-oxygen single bond of the ester is broken, just like in hydrolysis. Over the course of this reaction,
the ammonia replaces the alkoxy group of the ester. This produces an alcohol and a
compound that contains a carbonyl group bonded to a nitrogen atom. This functional group is called an
amide.
We now know that the hydrolysis of
esters using sodium hydroxide produces sodium carboxylates and alcohols, while the
ammonolysis of esters produces amides and alcohols. With this in mind, we should fill
in the first blank with sodium carboxylates and the second blank with amides.
