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Chapter 21. 2. Acid Derivatives. All can be converted to the carboxylic acid by acidic or basic hydrolysis.Esters and amides common in nature.. =>. Acid halide anhydride ester amide nitrile. Chapter 21. 3. Acid Anhydrides without water. Two molecules of acid combine with the loss of wate
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1. Chapter 21Carboxylic Acid Derivatives
2. Chapter 21 2 Acid Derivatives All can be converted to the carboxylic acid by acidic or basic hydrolysis.
Esters and amides common in nature.
3. Chapter 21 3 Acid Anhydrideswithout water Two molecules of acid combine with the loss of water to form the anhydride.
Anhydrides are more reactive than acids, but less reactive than acid chlorides.
A carboxylate ion is the leaving group in nucleophilic acyl substitution reactions.
4. Chapter 21 4 Interconversion ofAcid Derivatives Nucleophile adds to the carbonyl to form a tetrahedral intermediate.
Leaving group leaves and C=O regenerates.
5. Chapter 21 5 Reactivity Reactivity decreases as leaving group becomes more basic.
6. Chapter 21 6 Interconversion of Derivatives More reactive derivatives can be converted to less reactive derivatives.
7. Chapter 21 7 Acid Chloride to Anhydride Acid or carboxylate ion attacks the C=O.
Tetrahedral intermediate forms.
Chloride ion leaves, C=O is restored, H+ is abstracted. =>
8. Chapter 21 8 Acid Chloride to Ester Alcohol attacks the C=O.
Tetrahedral intermediate forms.
Chloride ion leaves, C=O is restored, H+ is abstracted. =>
9. Chapter 21 9 Acid Chloride to Amide Ammonia yields a 1? amide
A 1? amine yields a 2? amide
A 2? amine yields a 3? amide
10. Chapter 21 10 Anhydride to Ester Alcohol attacks one C=O of anhydride.
Tetrahedral intermediate forms.
Carboxylate ion leaves, C=O is restored, H+ is abstracted. =>
11. Chapter 21 11 Anhydride to Amide Ammonia yields a 1? amide
A 1? amine yields a 2? amide
A 2? amine yields a 3? amide
12. Chapter 21 12 Ester to Amide Nucleophile must be NH3 or 1? amine.
Prolonged heating required.
13. Chapter 21 13 Acid Chloride Reactions (1)
14. Chapter 21 14 Acid Chloride Reactions (2)