SCH4C – Organic Chemistry
533580613
Date: _______________________
Esters
Can be naturally occurring in plants and contribute to the _____________________
of fruits and flowers.
Uses: artificial/natural flavouring in foods, perfumes, cosmetics, oils, etc.
Esters can be made in the lab (___________________)
Has a carbonyl (C=O) group attached to an oxygen atom (bonded to an alkyl
group) and as well another alkyl group.
General Formula:
Esterification
How an ester is formed
Done by reacting a ______________________ with an ________________ in
presence of a catalyst (an acid) over heat
Small amounts of water is formed as well
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SCH4C – Organic Chemistry
533580613
Naming Esters
Form: (alcohol) (acid-anoate)
From the alcohol
Drop –anol, replace with “_____”
From the acid
Change from “______________” to “___________”
Example:
Draw the esterification reaction between methanol and ethanoic acid
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SCH4C – Organic Chemistry
533580613
Example: React methanol with butanoic acid
Drawing Esters
propylbutanoate
butylheptanoate
Draw the esterification reaction between propanol and hexanoic acid
Properties of Esters
Polar molecules (due to presence of O)
Lower melting points and boiling points than carboxylic acids and alcohols (they both
have OH groups = stronger)
Smaller esters are gases (the ones you smell) and large esters are solids
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SCH4C – Organic Chemistry
533580613
Draw structures for the following compounds.
1. ethylheptanoate
2. methyl-3-methylpentanoate
3. propyl-3-pentenoate
4. 3-methylbutyl-3-bromopropanoate
5. 3-methylpentyl-ethanoate
6. ethyl-ethanoate (ethyl-acetate)
7. methyl-hexanoate
8. 2-methylpropyl-octanoate
9. ethyl-5-hexynoate
10. 3-ethylpentyl-3-bromo-5-heptenoate
Name the following structures.
1.
6.
CH3CH2CH2CH2COOCH2CH3
CH3CH2CH2CH2CH2CH2CH2COOCH2CH2CH2CH2CH3
2.
7.
CH2CH3
|
CH3CH2CHCH2COOCH2CH2CH3
CH3CH=CHCH2COOCH3
8.
3.
CH3CH2CH2COOCH2CH2Br
CH≡CCHCOOCH2CH3
9.
4.
CH2=CHCH2COOCH2CH2CH3
CH2CH2CH3
|
CH3CH2CH2CHCH2CH2COOCH2CH2CH2CH2CH2CH3
5.
10.
Cl
|
CH3CHCH2COOCH3
Br
CH3
|
|
CH2CH=CHCH2COOCH2CHCH2CH3
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SCH4C – Organic Chemistry
533580613
Draw structural formulas to complete and balance the following reactions. Name the
ester produced.
1. butanoic acid + ethanol →
2. propanoic acid + methanol →
3. butanoic acid + 1-butanol →
4. ethanoic acid + methanol →
5. pentanoic acid + 2-butanol →
6. hexanoic acid + 2-propanol →
7. methanoic acid + 3-heptanol →
8. propanoic acid + 1-propanol →
9. ethanoic acid + 2-pentanol →
10. octanoic acid + ethanol →
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