Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Chapter 14 Carboxylic Acids, Esters, Amines, and Amides 14.1 Carboxylic Acids 1

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Carboxylic Acids A carboxylic acid contains a carboxyl group, which consists of a hydroxyl group  OH attached to the carbon in a carbonyl group. 2

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. IUPAC Names for Carboxylic Acids In the IUPAC names of carboxylic acids, the -e in the alkane name is replaced with -oic acid CH 4 Methane HCOOH Methanoic acid CH 3 —CH 3 Ethane CH 3 —COOH Ethanoic acid substituents are numbered from the carboxyl carbon 1 CH 3 O CH 3 —CH—CH 2 —C—OH methylbutanoic acid 3

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Common and IUPAC Names of Some Carboxylic Acids 4

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Common Carboxylic Acids Methanoic acid (formic acid) O H  C  OH Ethanoic acid (acetic acid) O CH 3  C  OH 5

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Naming Carboxylic Acids 6

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Naming Carboxylic Acids Give the IUPAC name for the following carboxylic acid. Step 1Identify the carbon chain containing the carboxyl group and replace the -e in the alkane name with -oic acid. Pentanoic acid 7

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Naming Carboxylic Acids Give the IUPAC name for the following carboxylic acid. Step 2 Give the location and name of each substituent on the main chain by counting the carboxyl carbon as 1. 2-methylpentanoic acid 8

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Aromatic Carboxylic Acids Benzoic acid is the simplest aromatic carboxylic acid locates substituents by numbering the ring from carbon 1 in the carboxyl group 9

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Alpha Hydroxy Acids (AHAs) Alpha hydroxy acids (AHAs) are naturally occurring carboxylic acids with a hydroxyl group (  OH) on the carbon adjacent to the carboxyl group. 10

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Alpha Hydroxy Acids (AHAs) Alpha hydroxy acids (AHAs) are used to remove acne scars and age spots were used by Cleopatra, Queen of Egypt, who bathed in sour milk, which contains lactic acid, an AHA 11

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Learning Check Give the IUPAC names of each compound. A. CH 3  CH 2  COOH B. CH 3 | CH 3  CH  CH 2  COOHC. 12

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Solution Give the IUPAC names of each compound. A. CH 3  CH 2  COOH propionoic acid B. CH 3 | CH 3  CH  CH 2  COOHC. 3-methylbutanoic acid 3-bromobenzoic acid 13

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Chapter 14 Carboxylic Acids, Esters, Amines, and Amides 14.2 Properties of Carboxylic Acids 14

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Polarity of Carboxylic Acids Carboxylic acids are strongly polar because they have two polar groups hydroxyl (  OH) and carbonyl (C=O) 15

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Solubility in Water Carboxylic acids form hydrogen bonds with many water molecules with one to four carbon atoms are very soluble in water as the number of carbons increases, the solubility of the carboxylic acid in water is reduced 16

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Solubility in Water 17

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Acidity of Carboxylic Acids Carboxylic acids are weak acids ionize in water to produce carboxylate ions and hydronium ions can lose a proton because two oxygen atoms in carboxylate ion stabilize negative charge O O CH 3  C  OH + H 2 O CH 3  C  O – + H 3 O + carboxylic acid carboxylate ion 18

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Learning Check Write the balanced equation for the ionization of butanoic acid in water and identify the carboxylate ion. 19

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Solution Write the balanced equation for the ionization of butanoic acid in water and identify the carboxylate ion. O O CH 3  CH 2  C  OH + H 2 O CH 3  CH 2  C  O – + H 3 O + carboxylic acid carboxylate ion 20

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Neutralization of Carboxylic Acids Carboxylic acid salts are a product of the neutralization of a carboxylic acid with a strong base CH 3 —COOH + NaOH CH 3 —COO – Na + + H 2 O acetic acid sodium acetate (carboxylic acid salt) are used as preservatives and flavor enhancers 21

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Carboxylic Acid Salts Carboxylic acid salts are used as preservatives and flavor enhancers such as sodium propionate, which is used in cheese and breads sodium benzoate, which inhibits growth of mold and bacteria and is added to fruit juices, margarine, relishes, salads, and jams monosodium glutamate, MSG, which is added to meats, fish, vegetables, and baked goods to enhance flavor 22

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Carboxylic Acid Salts 23

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Carboxylic Acid Salts Carboxylic acid salts are ionic compounds with strong attractive forces between ions are solids at room temperature have high melting points are usually soluble in water 24

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Learning Check Write the equation for the reaction of propanoic acid with A. water B. KOH 25

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Solution Write the equation for the reaction of propanoic acid with A. water CH 3 —CH 2 —COOH + H 2 O CH 3 —CH 2 —COO – + H 3 O + B. KOH CH 3 —CH 2 —COOH + KOH CH 3 —CH 2 —COO – K + + H 2 O 26

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Chapter 14 Carboxylic Acids, Esters, Amines, and Amides 14.3 Esters 27

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Esters Esters are found in fats and oils responsible for the aroma and flavor of bananas, oranges, and strawberries O  CH 3 —C—O—CH 3 ester group 28

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 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. 29

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 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. 30

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Learning Check Write the equation for the reaction of propanoic acid and methanol in the presence of an acid catalyst. 31

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Solution Write the equation for the reaction of propanoic acid and methanol in the presence of an acid catalyst. O  H + CH 3 —CH 2 —C—OH + H—O—CH 3 Propanoic acid Methanol O  CH 3 —CH 2 —C—O—CH 3 + H 2 O 32

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Naming Esters The name of an ester consists of two words derived from the name of the alcohol and the acid in that ester. 1.The first word indicates the alkyl part from the alcohol. 2.The second word is the carboxylate name of the carboxylic acid. 33

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Naming Esters Esters have IUPAC and common names: 34

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Guide to Naming Esters 35 What is the IUPAC name and common name of the following ester? O || CH 3  CH 2  CH 2  C  O  CH 2  CH 3

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Guide to Naming Esters 36 What is the IUPAC name of the following ester? Step 1 Write the name of the carbon chain from the alcohol as an alkyl group. O | CH 3  CH 2  CH 2  C  O  CH 2  CH 3 ethyl

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Guide to Naming Esters 37 What is the IUPAC name of the following ester? Step 2 Change the -ic acid of the acid name to -ate. O || CH 3  CH 2  CH 2  C  O  CH 2  CH 3 ethyl butanoate

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Learning Check Give the IUPAC and common names of the following compound, which is responsible for the flavor and odor of pears. O  CH 3 — C—O—CH 2 —CH 2 —CH 3 38

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Solution Give the IUPAC and common names of the following compound, which is responsible for the flavor and odor of pears. Step 1 Write the name of the carbon chain from the alcohol as an alkyl group. O  CH 3 —C—O—CH 2 —CH 2 —CH 3 propyl 39

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Solution Give the IUPAC and common names of the following compound, which is responsible for the flavor and odor of pears. Step 2 Change the -ic acid of the acid name to -ate. O  CH 3 —C—O—CH 2 —CH 2 —CH 3 propyl ethanoate (IUPAC) propyl acetate (common) 40

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Aspirin and Salicylic Acid Aspirin 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 41

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Esters in Fruits Esters give pleasant fragrances and flavors to many fruits and flowers. 42

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Learning Check Draw the structure of the following compounds. A. 3-bromobutanoic acid B. ethyl propionoate 43

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Solution A. 3-bromobutanoic acid Br O | || CH 3 —CH—CH 2 —C  OH B.ethyl propionoate O  CH 3 —CH 2 —C—O—CH 2 —CH 3 44

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Acid Hydrolysis of Esters In acid hydrolysis, an ester reacts with water to produce a carboxylic acid and an alcohol an acid catalyst is required O  H + H—C—O—CH 2 —CH 3 + H 2 O O  H—C—OH + H—O—CH 2 —CH 3 carboxylic acid alcohol formic acid ethanol 45

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Base Hydrolysis (Saponification) Base hydrolysis, or saponification, is the reaction of an ester with a strong base produces the salt of the carboxylic acid and an alcohol O || CH 3 —C—O—CH 2 —CH 3 + NaOH O  CH 3 —C—O – Na + + HO—CH 2 —CH 3 salt of carboxylic acid alcohol sodium acetate ethanol 46

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Base Hydrolysis of Fatty Acids Produces Soaps 47

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 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 48

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Learning Check Write the organic products when methyl acetate reacts with A. water and an acid catalyst B. KOH 49

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Solution Write the organic products when methyl acetate reacts with A. water and an acid catalyst O  H + CH 3 —C—O  CH 3 CH 3 —C—OH + HO—CH 3 B. KOH O O  Heat  CH 3 —C—O  CH 3 CH 3 —C—O – K + + HO—CH 3 50

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Chapter 14 Carboxylic Acids, Esters, Amines, and Amides 14.4 Amines 51

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Amines are derivatives of ammonia, NH 3 contain N attached to one or more alkyl or aromatic groups CH 3 CH 3  CH 3 —NH 2 CH 3 —NH CH 3 —N—CH 3 52

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 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 3 CH 3 | | | CH 3 —N—H CH 3 —N—H CH 3 —N—CH 3 1° 2° 3° 53

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Skeletal Structures of Amines The skeletal structures show the shapes of amine molecules with one or more alkyl groups bonded to the nitrogen atom. 54

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 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 CH 3 —CH 2 —NH 2 Ethylamine CH 3 —NH—CH 3 Dimethylamine CH 3 | CH 3 —N—CH 2 —CH 3 Ethyldimethylamine 55

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Learning Check Give the common name and classify as primary, secondary, or tertiary. A. CH 3 —CH 2 —CH 2 —NH 2 CH 3 | B. CH 3 —CH 2 —N—CH 3 56

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Solution A. CH 3 —CH 2 —CH 2 —NH 2 propylamine, 1  CH 3 | B.CH 3 —CH 2 —N—CH 3 ethyldimethylamine, 3  57

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Aromatic Amines The amine of benzene is named aniline. Alkyl groups on the N use the prefix N− with alkyl name. N-methylaniline aniline 3-chloroaniline 58

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Learning Check Give the common name of each compound. A. CH 3 —NH—CH 2 —CH 3 CH 3 | B.CH 3 —CH 2 —N—CH 2 —CH 3 C. 59

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Solution Give the common name of each compound. A. CH 3 —NH—CH 2 —CH 3 ethylmethylamine CH 3 | B.CH 3 —CH 2 —N—CH 2 —CH 3 C. diethylmethylamine aniline 60

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 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 61

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 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. CH 3 —CH 2 —CH 2 —NH 2 B. CH 3 —CH 2 —NH—CH 3 C. CH 3 —CH 2 —CH 2 —CH 3 62

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Solution Consider the compounds below: 1. Which compound cannot form hydrogen bonds with other amines? CH 3 —CH 2 —CH 2 —CH 3 C is an alkane, which cannot form hydrogen bonds with each other. 2. Which compound is not soluble in water? CH 3 —CH 2 —CH 2 —CH 3 C is an alkane and therefore not soluble in water. 63

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Amines React as Bases Like ammonia, amines are weak bases in water. NH 3 + H 2 O NH OH – ammonium ion hydroxide ion CH 3 —NH 2 + H 2 O CH 3 —NH OH – methylammonium ion hydroxide ion 64

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 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 65

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Neutralization Forms Amine Salts 66

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Properties of Amine Salts Amine salts are solids at room temperature soluble in water and body fluids the form used for drugs 67

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 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 68

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 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. 69

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 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 70

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Caffeine is a stimulant of the central nervous system is found in coffee beans, tea, chocolate, and soft drinks 71

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Nicotine increases the adrenaline level in the blood causes addiction to tobacco 72

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Morphine and Codeine Morphine and codeine are alkaloids obtained from the oriental poppy plant used as painkillers modified to make heroin 73

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Learning Check Write the structural formula for A. methylpropylamine B. 2-chloroaniline 74

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Solution A. methylpropylamine CH 3 –CH 2 –CH 2 –NH–CH 3 B. 2-chloroaniline 75

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Chapter 14 Carboxylic Acids, Esters, Amines, and Amides 14.5 Amides 76

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Amides Amides are derivatives of carboxylic acids in which a nitrogen group (–NH 2 ) replaces the –OH group of carboxylic acids. O O || || CH 3 —C—OH CH 3 —C—NH 2 77

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Preparation of Amides Amides are produced by reacting a carboxylic acid with ammonia or a 1  or 2  amine with heat. 78

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 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—NH 2 formamide (common) O  propanamide (IUPAC) CH 3 —CH 2 —C—NH 2 propionamide (common) 79

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 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  │ CH 3 —C—N—CH 3 N-methylethanamide (IUPAC) N-methylacetamide (common) O H  │ CH 3 —CH 2 —C—N—CH 2 —CH 3 N-ethylpropanamide (IUPAC) N-ethylpropionamide (common) 80

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Aromatic Amide The aromatic amine is benzamide. Benzamide 81

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Learning Check Give the IUPAC and common names for the following. O  A. CH 3 –CH 2 –CH 2 –C–NH 2 O H  │ B. CH 3 –C–N–CH 2 –CH 3 82

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Solution O  A. CH 3 –CH 2 –CH 2 –C–NH 2 butanamide (IUPAC) butryamide (common) O H  │ B. CH 3 –C–N–CH 2 –CH 3 N-ethylethanamide (IUPAC) N-ethylacetamide (common) 83

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Learning Check Draw the structures of the following. A.pentanamide B.N-methylbutyramide 84

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Solution A.pentanamide O  CH 3 –CH 2 –CH 2 –CH 2 –C–NH 2 B.N-methylbutyramide O  CH 3 –CH 2 –CH 2 –C–NH–CH 3 85

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 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. 86

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Some Amides in Health and Medicine 87

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 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. 88

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Hydrolysis of Amides Amides undergo acid hydrolysis to produce a carboxylic acid and an ammonium salt base hydrolysis to produce the salt of a carboxylic acid and an amine or ammonia 89

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Hydrolysis Reactions 90

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Learning Check Write the products of the hydrolysis of N-ethylpropanamide with NaOH. 91

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Solution Write the products of the hydrolysis of N-ethylpropanamide with NaOH. O  CH 3 —CH 2 —C—NH  CH 2 —CH 3 + NaOH O  CH 3 —CH 2 —C—O – Na + + CH 3 —CH 2 —NH 2 92