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Ch 13 Carboxylic Acids, Esters,
Amines and Amides
SWBAT:
Name/Draw compounds with functional groups
Describe/Explain properties of functional groups
Complete/Show reactions of functional groups
Chapter 13.3
Esters
Esters
• Carboxylic acid react with an alcohol to
form an ester
Carboxylic Acid
Alcohol
Ester
• The aromas and flavors of many fruits
are due to esters
Esterification
• Occurs when a carboxylic acid reacts with an
alcohol and is heated in the presence of an
acid catalyst (usually H2SO4)
• In this Reaction, water is produced from the
–OH removed from the carboxylic acid and an
–H lost by the alcohol
Naming Esters
carboxylic acid
alcohol
• Determine the longest carbon chain that
belongs to the alcohol (Ethyl – from ethanol)
• Determine the longest carbon chain that
contains the carbonyl and name it as a
carboxylic acid (propanoic acid)
• Change the acid ending from “-ic” to “-ate”
(propanoate)
• Combine the alcohol name followed by the
acid name (Ethyl propanoate)
Practice Naming
ethyl 3-bromo-2chloropropanoate
ethyl 2-bromopropanoate
3-methylbutyl butanoate
Properties of Esters
• Esters do not have a hydroxyl (OH) group – so
they can not form H-bonds
– Boiling point is lower than carboxylic acids & alcohols
Acid Hydrolysis of Esters
• In acid hydrolysis esters are split apart with
water when heated in the presence of a
strong acid (usually H2SO4 or HCl)
– The products are carboxylic acid and alcohol
• This is the reverse of esterification rxn
Base Hydrolysis of Esters
• In base hydrolysis esters are split apart with
heat in the presence of a strong base (usually
NaOH or KOH)
– The products are carboxylic acid salt and alcohol
• This is called saponification
Base Hydrolysis of Esters
• The carboxylic acid that is produced in acid
hydrolysis is converted in an irreversible
reaction to a carboxylate ion by the strong
base
Homework
Chapter 13
Page 439 13.18 – 13.32 (even)