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Esters and Esterification
Esters produced by combining carboxylic acid andalcohol (esterification)
Large chain esters account for flavor and odor of fruits.
General formula: R–COOR'
R - hydrocarbon chain from the acid R' - hydrocarbon chain from the alcohol.
alcoholcarboxyl acid
H
C-C
O
O H O-C
ester
water
Esterification is a reversible reaction.
De-esterification reaction
esterification reaction
H
O
H
O-CC-C
O
+
ester
alcohol
carboxyl acid
H
C-C
O
O H
O-C
· First name alcohol: change "anol" to "yl"· Second name acid: change "ioc acid" to "oate"
Naming Esters
2 – names:
CH3COOCH2CH2CH3
propyl ethanoate
CH3-C
O
\O-CH2CH2CH3
//alcohol
acid
CH3CH2CH2CO + OCH3
butanoic acid methanol
CH3CH2CH2COOCH3 + H2O
methyl butanoate water
OH H
CH3CH2CH2CH2CH2COOCH2CH2CH2CH3
butyl hexanoate
Write the esterification reaction for the reactionbetween pentanoic acid and 1-butanol.
Esters are polar molecules but have NO hydrogen bonding (unlike alcohols, carboxylic acids, water)
Bp / mp are higher than aliphatics but lower than acids and alcohols.
Esters are soluble in water.
• Esterification carboxylic acid and an alcohol thatproduces an ester and water.
• General formula RCOOR' ( R acid, R' alcohol).
• Name is two words: the alkyl group from alcohol,then acid with replaced ending - oate.
• Polar but do not hydrogen bond. Lower melting points and boiling points than acids and alcohols.
• Soluble in water.
Hydroxide ions also catalyze the breakdown ofesters.
salt