Carboxylic Acids

1
Carboxylic Acids

• 1. -OH group added to carbonyl group produces
  carboxyl group
• 2. May be attached to alkyl or aromatic
• ethanoic acid methanoic acid
• (acetic acid) (formic acid)

2
Carboxylic Acid Nomenclature

• 1. Longest C chain with carboxyl group is parent
  chain
• 2. Replace -e in parent name with -oic acid
• 3. Carboxyl C is C1
• 4. Number name side groups appropriately

3
Carboxylic Acid Nomenclature Examples

• 3-methylbutanoic acid
• 
  benzoic acid

4
Carboxylic Acids Synthesis

• 1. Oxidation of aldehyde produces carboxylic acid
• 2. Complete oxidation of alcohol produces
  aldehyde, then carboxylic acid
• ethanol ethanal
  ethanoic acid
• (acetaldehyde)
  (acetic acid)

5
Carboxylic Acid Properties

• 1. Solubility
• 2. Ionization
• 3. Neutralization

6
Carboxylic Acid Solubility

• 1. Hydroxyl group and carbonyl group polar
• 2. Short chain carboxylic acids, C1 to C4 are
  very water soluble
• 3. Long chain carboxylic acids, C5 and up are
  slightly water soluble

7
Carboxylic Acid Ionization

• 1. Donate H to H2O to form H3O
• 2. Weak acids, but gt phenols
• 3. Negative ion is referred to as carboxylate ion

8
Carboxylate Ion Example

• 1. Donate H to H2O to form H3O
• 2. Weak acids, but gt phenols
• 3. Negative ion is referred to as carboxylate ion
• ethanoic acid ethanoate ion
• (acetic acid) (acetate ion)

9
Carboxylic Acid Neutralization

• 1. Base carboxylic acid produce carboxylic acid
  salt H2O
• 2. Carboxylic acid salt is more H2O soluble than
  carboxylic acid

10
Neutralization

• methanoic sodium
  methanoate
• acid
  (sodium formate)
• benzoic acid sodium
  benzoate

11
Organic Salts

• copper ( I ) naphthalate

benzyl ammonium chloride
12
Esters

• 1. Carboxylic acid alcohol produce ester
• 2. Requires T H, usually H2SO4
• 3. -OH from carboxylic acid and -H from alcohol
  produce H2O
• 4. Found in many plants, taste smell

13
Esterification

• ethanoic methanol methyl ethanoate
• acid

14
Ester Nomenclature

• 1. Name alkyl group from alcohol, then carboxylic
  acid
• 2. Change -ic to -ate
• methyl ethanoate ethyl
  methanoate
• (methyl acetate)
  (ethyl formate)

15
Ester Hydrolysis

• 1. Acid hydrolysis
• 2. Base hydrolysis

16
Acid hydrolysis

• 1. Produces carboxylic acid and alcohol
• methyl benzoic
  methanol
• benzoate acid

17
Base hydrolysis

• 1. Saponification- produces salt of carboxylic
  acid (soap) alcohol
• methyl sodium
  methanol
• propanoate propanoate

18
Amines

• 1. One, 2, or 3 alkyl /or aromatic groups
  attached to N
• 2. Biogenic amines- histamines, epinephrine,
  norepinephrine, dopamine, serotonin
• 3. 1o, 2o, 3o amines

19
1o, 2o, 3o amines

• 1o amine
• 2o amine
  
• 3o amine

20
Amine Nomenclature

• 1. Longest/largest carbon chain/ring is parent ,
  N-C is C1
• 2. Remaining alkyl or aromatic groups attached to
  N, named as N-substituents
• 3. If identical, use di- tri-
• 4. If different, arrange alphabetically

21
Amine Nomenclature Examples

• N-methylethylamine
• (ethylmethylamine) N,N-dimethylethylami
  ne
• 1-methylbutylamine
• (2-aminobutane)
  

22
Aromatic Amines

• aniline
• N-methylaniline

23
Alkaloids

• 1. Physiologically active amines produced by
  plants or fungi
• 2. Quinine, nicotine, cocaine, caffeine,
  morphine, mescaline, lysergic acid diethylamide

24
Amine Solubility

• 1. N makes amines polar
• 2. All 1o 2o amines are water soluble
• 3. 3o amines up to 5 carbons are water soluble

25
Amine Reactions

• 1. Ionization
• 2. Neutralization
• 3. Amidation

26
Amine Ionization

• 1. Amines are weak bases, N atoms e- pair
  accepts H ion
• aminomethane methylammonium
• (methylamine) ion

27
Amine Neutralization

• 1. Amine inorganic acid produce ammonium salt
• aminomethane methylammonium
• 
  chloride

28
Amidation

• 1. Amine or ammonia carboxylic acid produce
  amide
• 2. Only 1o 2o amines, requires
• H-N bond

29
Amidation Example1

• ethanoic ammonia ethanamide
• acid
  (acetamide)
• (acetic acid)

30
Amidation Example2

• ethanoic aminomethane N-methylethanamide
• acid (methylamine) (N-methyl
  acetamide)
• (acetic acid)

31
Amide Examples

• propanamide
• 
  N-methylpropanamide

32
Amide Nomenclature

• 1. Name parent amine as alkyl using N to show
  position
• 2. Carbonyl C is C1
• 3. Rename parent acid as amide
• 4. Use two N,N, if more than one carbon
  chain/ring attached to N
• 5. If identical, use di- tri-
• 6. If different, arrange alphabetically

33
Amide Nomenclature Examples

• 4-methylpentanamide
• 
  N-methylbenzamide
• N,N-dimethyl-2-bromobutanamide

34
Amide Reactions

• 1. Acid Hydrolysis
• 2. Base Hydrolysis

35
Acid Hydrolysis of Amide

• 1. Amide, inorganic acid, H2O produces
  carboxylic acid ammonium salt
• 
  ethanoic acid
• 
  (acetic acid)
• ethanamide
  ammonium
• (acetamide)
  chloride

36
Base Hydrolysis of Amide

• 1. Amide base produces carboxylate salt
  ammonia or alkylamine
• sodium
  propanoate
• N-methylpropanamide aminomethane