1 17.4 esters of carboxylic acids 17.5 naming esters 17.6 properties of esters chapter 17 carboxylic...
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17.4 Esters of Carboxylic Acids
17.5 Naming Esters
17.6 Properties of Esters
Chapter 17 Carboxylic Acids And Esters
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In an ester, the H in the carboxyl group is replaced by an alkyl group.
O CH3—C—O—CH3
CH3—COO—CH3
ester group
Esters
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An ester is produced by the reaction of a carboxylic acid and alcohol in the presence of an acid catalyst.
O H+
CH3—C—OH + HO—CH2—CH3
O
CH3—C—O—CH2—CH3 + H2O
Esterification
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Ester Products
Aspirin: Is used to relieve pain and
reduce inflammation. Is an ester of salicylic acid
and acetic acid.Oil of wintergreen: Is used to soothe sore
muscles. Is an ester of salicylic acid
and methanol.
C
O
OH
O C
O
CH3
Acetylsalicylic acid(Aspirin)
C
O
O CH3
OH
Methyl salicylate(Oil of wintergreen)
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Esters are named with the alkyl name of the alcohol followed by the carboxylate name from the acid.
from acid from alcohol O
methylCH3—C—O—CH3
Ethanoate methyl ethanoate (IUPAC) (Acetate) methyl acetate (common)
Naming Esters
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In hydrolysis: An ester reacts with water to produce a carboxylic
acid and an alcohol. An acid catalyst is required.
O H+
H—C—O—CH2—CH3 + H2O
O
H—C—OH + HO—CH2—CH3
Hydrolysis
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In base hydrolysis or saponification, an ester reacts with a strong base to produce the salt of the carboxylic acid and an alcohol. O
|| CH3—C—O—CH2—CH3 + NaOH
O CH3—C—O– Na+ + HO—CH2—CH3
salt of carboxylic acid alcohol
Base Hydrolysis (Saponification)