1. CH part 2

2. Chapter 14 Carboxylic Acids, Esters, Amines, and Amides
14.3
Esters

3. Esters Esters are found in fats and oils
responsible for the aroma and flavor of bananas, oranges, and strawberries O 
CH3 —C—O—CH3
ester group

4. Esterification
Esterification is the reaction of a carboxylic acid and alcohol in the presence of an acid catalyst to produce an ester. The main chain of an ester comes from the carboxylic acid, while the alkyl group in an ester comes from the alcohol.

5. Esterification
An example of esterification is the reaction of a ethanoic acid with 1-propanol to produce an ester called propylethanoate, responsible for the smell of pears.

6. Naming Esters
Esters have IUPAC and common names:

7. Learning Check
Give the IUPAC and common names of the following compound, which is responsible for the flavor and odor of pears. O  CH3 — C—O—CH2—CH2—CH3

8. Aspirin and Salicylic Acid
is used to relieve pain and reduce inflammation
is an ester of salicylic acid and acetic acid
Oil of wintergreen
is used to soothe sore muscles
is an ester of salicylic acid and methanol

9. Esters in Fruits
Esters give pleasant fragrances and flavors to many fruits and flowers.

10. Solution
A. 3-bromobutanoic acid Br O | || CH3—CH—CH2—COH B. ethyl propionoate O  CH3—CH2 —C—O—CH2—CH3

11. Base Hydrolysis of Fatty Acids Produces Soaps

12. Cleaning Action of Soap
A soap
contains a nonpolar end that dissolves in nonpolar fats and oils, and a polar end that dissolves in water
forms groups of soap molecules called micelles that dissolve in water and are washed away

13. Chapter 14 Carboxylic Acids, Esters, Amines, and Amides
14.4
Amines

14. Amines Amines are derivatives of ammonia, NH3
contain N attached to one or more alkyl or aromatic groups
CH3 CH3
 
CH3—NH CH3—NH CH3—N—CH3

15. Classification of Amines
Amines are classified as primary, secondary, or tertiary:
a primary (1) amine has one carbon group bonded to the nitrogen atom
a secondary (2) amine has two carbon groups bonded to the nitrogen atom
a tertiary (3) amine has three carbon groups bonded to the nitrogen atom
H CH CH3
| | |
CH3—N—H CH3—N—H CH3—N—CH3
1° ° °

16. Skeletal Structures of Amines
The skeletal structures show the shapes of amine molecules with one or more alkyl groups bonded to the nitrogen atom.

17. Naming Amines Simple amines are named as alkylamines
list the names of the alkyl groups bonded to the N atom
in alphabetical order in front of amine
CH3—CH2—NH2 Ethylamine
CH3—NH—CH3 Dimethylamine
CH3 |
CH3—N—CH2—CH3 Ethyldimethylamine

18. Learning Check Give the common name of each compound.
A. CH3—NH—CH2—CH3
CH3 |
B. CH3—CH2—N—CH2—CH C.

19. Properties of Amines 1 and 2 amines
can form hydrogen bonds with each other and water molecules
can form hydrogen bonds, while amines with less than six carbons are soluble in water because they form hydrogen bonds with water
3 amines can only form hydrogen
bonds with water molecules

20. Learning Check
Consider the compounds below: 1. Which compound cannot form hydrogen bonds with other amines? 2. Which compound is not soluble in water? A. CH3—CH2—CH2—NH2 B. CH3—CH2—NH—CH3 C. CH3—CH2—CH2—CH3

21. Solution
Consider the compounds below: 1. Which compound cannot form hydrogen bonds with other amines? CH3—CH2—CH2—CH3 C is an alkane, which cannot form hydrogen bonds with each other. 2. Which compound is not soluble in water? CH3—CH2—CH2—CH3 C is an alkane and therefore not soluble in water.

22. Neutralization Forms Amine Salts
An amine salt
forms when amines such as those responsible the odor in fish are neutralized by acid such as citric acid in lemons
is named by replacing the amine part of the name with ammonium, followed by the name of the negative ion

23. Neutralization Forms Amine Salts

24. Properties of Amine Salts
Amine salts are
solids at room temperature
soluble in water and body fluids
the form used for drugs

25. Alkaloids Alkaloids are
physiologically active nitrogen-containing compounds produced by plants such as cocaine
compounds that are alkali-like or have basic characteristics like amines
used as anesthetics, as antidepressants, and in stimulants such as caffeine, and may be habit forming

26. Alkaloids: Cocaine
Cocaine is extracted from plants by reacting them with hydrochloric acid and producing cocaine hydrochloride.
When cocaine hydrochloride is treated with NaOH and ether it is called free-basing. This reaction produces “crack cocaine,” a free amine or free base of the amine.

27. Heterocyclic Amines A heterocyclic amine
is a cyclic compound that contains one or more nitrogen atoms in a ring
typically consists of five or six atoms in the ring with one or more nitrogen atoms

28. Caffeine Caffeine is a stimulant of the central nervous system
is found in coffee beans, tea, chocolate, and soft drinks

29. Nicotine Nicotine increases the adrenaline level in the blood
causes addiction to tobacco

30. Morphine and Codeine Morphine and codeine are alkaloids
obtained from the oriental poppy plant
used as painkillers
modified to make heroin

31. Solution
A. methylpropylamine CH3–CH2–CH2–NH–CH3
B. 2-chloroaniline

32. Chapter 14 Carboxylic Acids, Esters, Amines, and Amides

33. Amides
Amides are derivatives of carboxylic acids in which a nitrogen group (–NH2) replaces the –OH group of carboxylic acids. O O || || CH3—C—OH CH3—C—NH2

34. Preparation of Amides
Amides are produced by reacting a carboxylic acid with ammonia or a 1 or 2 amine with heat.

35. Naming Amides
For IUPAC naming, the -oic acid from the carboxylic acid name ending is replaced with -amide
For common names, the -ic acid from the carboxylic acid name ending is replaced with -amide O
 methanamide (IUPAC)
H—C—NH2 formamide (common)
 propanamide (IUPAC)
CH3—CH2—C—NH2 propionamide (common)

36. Naming Amides with N Groups
An alkyl group attached to the nitrogen of an amide is named with the prefix N-, followed by the alkyl name. O H  │ CH3 —C—N—CH3 N-methylethanamide (IUPAC) N-methylacetamide (common) O H CH3—CH2 —C—N—CH2—CH3 N-ethylpropanamide (IUPAC) N-ethylpropionamide (common)

37. Solution
A. pentanamide O  CH3–CH2–CH2–CH2–C–NH2 B. N-methylbutyramide CH3–CH2–CH2–C–NH–CH3

38. Some Amides in Health and Medicine
Urea is the end product of protein metabolism.
Saccharin is an artificial sweetener.
Some amides, such as phenobarbital (Luminal) and pentobarbital (Nembutal), are barbiturates.
Acetaminophen is used to reduce fever and pain.

39. Some Amides in Health and Medicine

40. Solubility of Amides
Amides with one to five carbon atoms are soluble in water because they can form hydrogen bonds with water molecules. Hydrogen bonding effects are diminished when molecules have more than five carbon atoms, therefore reducing solubility.

41. Hydrolysis Reactions

42. Chapter 15 Lipids
15.1
Lipids

43. Lipids
Lipids are
biomolecules that contain fatty acids or a steroid nucleus
soluble in organic solvents, but not in water
named for the Greek word lipos, which means “fat”
extracted from cells using organic solvents
an important feature in cell membranes, fat-soluble vitamins, and steroid hormones

44. Types of Lipids
There are different types of lipids. 1. Lipids such as waxes, fats, oils, and glycerophospholipids are esters that can be hydrolyzed to give fatty acids and alcohols. 2. Steroids are also lipids; they do not contain fatty acids and cannot be hydrolyzed. They are characterized by the steroid nucleus of four fused carbon rings.

45. General Structure of Lipids
Lipids are naturally occurring compounds that are soluble in organic solvents but not in water.

46. Learning Check
There are two types of lipids, fatty acids and steroids. Which
type is described by the following?
A. contains a four-membered ring system
B. contains long carbon chains
C. includes triacylglycerols

47. Solution
There are two types of lipids, fatty acids and steroids. Which
type is described by the following?
A. contains a four-membered ring system steroids
B. contains long carbon chains fatty acids
C. includes triacylglycerols fatty acids

48. Learning Check
Which of the following is NOT a characteristic of lipids?
A. may contain a carboxylic acid group
B. may contain a four-ring structure
C. soluble in water
D. mostly nonpolar

49. Solution Which of the following is NOT a characteristic of lipids?
The answer is C. Lipids are nonpolar and therefore are NOT
soluble in water.

50. Chapter 15 Lipids
15.2
Fatty Acids

51. Fatty Acids Fatty acids are long-chain carboxylic acids
typically 12–18 carbon atoms
insoluble in water
saturated or unsaturated
Olive oil contains 84% unsaturated fatty acids and 16% saturated fatty acids.

52. Saturated and Unsaturated Fatty Acids
Fatty acids can be
saturated, with all single C–C bonds
monounsaturated, with one double C=C bond
polyunsaturated, with more than one double C=C bond

53. Properties of Saturated Fatty Acids
contain only single C–C bonds and fit close together in a regular pattern
have strong attractions between long carbon chains
have higher melting points and are usually solids at room temperature

54. Properties of Saturated Fatty Acids
In saturated fatty acids, the molecules fit closely together to give high melting points.

55. Properties of Unsaturated Fatty Acids
contain one or more cis double C=C bonds
have “kinks” in the fatty acid chains
do not pack closely
have few attractions between chains
have low melting points
are liquids at room temperature
“kinks” in chain

56. Properties of Unsaturated Fatty Acids
In unsaturated fatty acids, molecules cannot fit closely together, resulting in lower melting points.

57. Melting Points of Some Saturated Fatty Acids

58. Melting Points of Some Unsaturated Fatty Acids

59. Learning Check stearic acid (18 carbons) saturated
Assign the melting points of –17 C, 13 C, and 69 C to the correct fatty acid. Explain.
stearic acid (18 carbons) saturated
oleic acid (18 carbons) one double bond
linoleic acid (18 carbons) two double bonds

60. Solution
Stearic acid is saturated and would have a higher melting point than the unsaturated fatty acids. Because linoleic has two double bonds, it would have a lower mp than oleic acid, which has one double bond.
stearic acid mp 69 C saturated
oleic acid mp 13 C
linoleic acid mp –17 C most unsaturated

61. Prostaglandins Prostaglandins
are hormone-like substances produced in cells
are also known as eicosanoids, formed from arachidonic acid, the polyunsaturated fatty acid with 20 carbon atoms
differ by the substituents attached to the five-carbon ring
have many functions, such as lower or raising blood pressure and stimulating contraction and relaxation of uterine smooth muscle

62. Prostaglandins
When tissues are injured, arachidonic acid is converted to prostaglandins such as PGE and PGF that produce inflammation and pain in the area.

63. Prostaglandins: NSAIDs
The treatment of pain, fever, and inflammation is based on inhibiting the enzymes that convert arachidonic acid to prostaglandins.

64. Prostaglandins: NSAIDs
Nonsteroidal anti-inflammatory drugs (NSAIDs) block production of prostaglandins, decreasing pain and inflammation.

65. Omega-3 Fatty Acids
Unsaturated fats such as those in vegetable oils and fish are recognized as more beneficial to health than saturated fats. Vegetables contain omega-6 acids, meaning the first double bond occurs at carbon 6. Examples of omega-6 acids are linoleic and arachidonic acids.

66. Omega-3 Fatty Acids
Fish have high levels of omega-3 acids, meaning the first double bond occurs at carbon 3. Examples of omega-3 acids include linolenic, eicosapentaenoic, and docosahexaenoic acids.
Cold-water fish are a source of omega-3 fatty acids.

67. Omega-3 and Omega-6 Fatty Acids

68. Chapter 15 Lipids 15.3 Waxes, Fats, and Oils
Waxes are esters of long-chain alcohols and fatty acids.

69. Waxes
Waxes are
esters of saturated fatty acids and long-chain alcohols
coatings that prevent loss of water by leaves of plants

70. Fats and Oils: Triacylglycerols
Fats and oils are
also called triacylglycerols
esters of glycerol
produced by esterification
formed when the hydroxyl groups of glycerol react with the carboxyl groups of fatty acids

71. Triacylglycerols
In a triacylglycerol, glycerol forms ester bonds with three fatty acids.

72. Formation of a Triacylglycerol
In a triacylglycerol, three hydroxyl groups on a glycerol molecule form ester bonds with the carboxyl groups of three fatty acids.

73. Melting Points of Fats and Oils
A fat
is usually solid at room temperature
is prevalent in meats, whole milk, butter, and cheese
An oil
is usually liquid at room temperature
is prevalent in plants such as olive and safflower

74. Oils with Unsaturated Fatty Acids
have more unsaturated fats
have cis double bonds that cause “kinks” in the fatty acid chains
with “kinks” in the chains do not allow the triacylglycerol molecules to pack closely
have lower melting points than saturated fatty acids
are liquids at room temperature

75. Diagram of Triacylglycerol with Unsaturated Fatty Acids
Unsaturated fatty acid chains with kinks cannot pack closely.

76. Percent Saturated and Unsaturated Fatty Acids in Fats and Oils
Vegetable oils have low melting points because they have a higher percentage of unsaturated fatty acids than do animal fats.