1. Chapter 21 Carboxylic Acid Derivatives (continued)
Organic Chemistry, 6th Edition L. G. Wade, Jr.
Chapter 21 Carboxylic Acid Derivatives (continued)

2. Hydrolysis of Acid Chlorides and Anhydrides
Hydrolysis occurs quickly, even in moist air with no acid or base catalyst.
Reagents must be protected from moisture.
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3. Acid Hydrolysis of Esters
Reverse of Fischer esterification.
Reaches equilibrium.
Use a large excess of water.
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4. Saponification Base-catalyzed hydrolysis of ester.
“Saponification” means “soap-making.”
Soaps are made by heating NaOH with a fat (triester of glycerol) to produce the sodium salt of a fatty acid - a soap.
One example of a soap is sodium stearate, Na+ -OOC(CH2)16CH =>
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5. Hydrolysis of Amides
Prolonged heating in 6 M HCl or 40% aqueous NaOH is required.
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6. Hydrolysis of Nitriles
Under mild conditions, nitriles hydrolyze to an amide.
Heating with aqueous acid or base will hydrolyze a nitrile to an acid.
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7. Reduction to Alcohols
Lithium aluminum hydride reduces acids, acid chlorides, and esters to primary alcohols.
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8. Reduction to Aldehydes
Acid chlorides will react with a weaker reducing agent to yield an aldehyde.
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9. Reduction to Amines
Lithium aluminum hydride reduces amides and nitriles to amines.
Nitriles and 1 amides reduce to 1 amines.
A 2 amide reduces to a 2 amine.
A 3 amide reduces to a 3 amine.
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10. Organometallic Reagents
Grignard reagents and organolithium reagents add twice to acid chlorides and esters to give alcohols after protonation.
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11. Grignard Reagents and Nitriles
A Grignard reagent or organolithium reagent attacks the cyano group to yield an imine which is hydrolyzed to a ketone.
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12. Acid Chloride Synthesis
Use thionyl chloride, SOCl2, or oxalyl chloride, (COCl)2.
Other products are gases.
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13. Acid Chloride Reactions (1)
ester
amide
acid anhydride
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14. Acid Chloride Reactions (2)
3° alcohol
ketone
1° alcohol
aldehyde
acylbenzene
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AlCl3

15. Lab Synthesis of Anhydrides
React acid chloride with carboxylic acid or carboxylate ion.
Heat dicarboxylic acids to form cyclic anhydrides.
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16. Anhydride Reactions acid ester amide acylbenzene => AlCl3
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17. Anhydride vs. Acid Chloride
Acetic anhydride is cheaper, gives a better yield than acetyl chloride.
Use acetic formic anhydride to produce formate esters and formamides.
Use cyclic anhydrides to produce a difunctional molecule.
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18. Synthesis of Esters acid acid chloride acid anhydride =>
methyl ester
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19. Reactions of Esters acid ester amide 1° alcohol 3° alcohol =>
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20. Lactones Formation favored for five- and six-membered rings.
For larger rings, remove water to shift equilibrium toward products
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21. Polyesters Dacron® thread Mylar® tape Glyptal resin PET bottles =>
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22. Synthesis of Amides acid acid chloride acid anhydride ester nitrile
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23. Reactions of Amides acid and amine amine 1° amine nitrile =>
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24. Lactam Formation
Five- and six-membered rings can be formed by heating - and -amino acids.
Smaller or larger rings do not form readily =>
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25. End of Chapter 21
Chapter 21