Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 1 Classification of Amines Amines are basic nitrogen-containing compounds that are derivatives of ammonia. Amines are classified as: Primary (the nitrogen atom has one hydrocarbon group directly attached) Secondary (the nitrogen atom has two hydrocarbon groups directly attached) Tertiary (the nitrogen atom has three hydrocarbon groups directly attached). Amines

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 2 Examples of primary (1 o ), secondary (2 o ) and tertiary (3 o ) amines are shown here. Amines: Nomenclature and Physical Properties

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 3  Classify the following amines as 1 o, 2 o or 3 o. Your Turn!

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 4  Classify the following amines as 1 o, 2 o or 3 o. Your Turn!

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 5 IUPAC Rules for Naming Amines 1.Name the longest continuous carbon chain containing the amine group. The carbon atom attached to the amine group is the #1 carbon atom. 2.Drop –e from the corresponding alkane and add the suffix –amine. Amines: Nomenclature and Physical Properties

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 6 Here are some examples of primary amines. Amines: Nomenclature and Physical Properties

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc Use a prefix with a capital N (italicized) if the amine nitrogen atom has an alkyl group or other group attached (2 o and 3 o amines). Amines: Nomenclature and Physical Properties

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 8 Simple amines are most often referred to by their common names. The common names for aliphatic amines are formed by naming the alkyl group or groups attached to the nitrogen atom, followed by the ending – amine. Amines: Nomenclature and Physical Properties

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 9 The common names of some amines are shown here. Amines: Nomenclature and Physical Properties

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 10 The most important aromatic amine is aniline (C 6 H 5 NH 2 ). Derivatives are named as substituted anilines. Amines: Nomenclature and Physical Properties

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 11  Give names for the following amines. Your Turn!

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 12  Give names for the following amines. Your Turn!

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Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 17 Chemical Properties of Amines Alkaline Properties of Amines Amines resemble ammonia in their reactions. Amines are bases, and like ammonia, produce OH - ions in water สารละลาย เป็นเบส

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 18 Salt Formation Because amines are weak bases, they react with strong acids to form ammonium salts. Methylamine for example reacts with strong acid yielding the corresponding methylamonium salt. Chemical Properties of Amines

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 19 Chemical Properties of Amines Methylammonium chloride is a white crystalline solid made up of methylammonium ions, CH 3 NH 3 +, and chloride ions, Cl -. Many amines or amino compounds are more stable in the form of the hydrochloride salt. When the free amine is wanted, the HCl is neutralized to liberate the free amine.

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 20 Sources and Uses of Selected Amines Biogenic amines are derived from amino acids and act as neurotransmitters and hormones in animals. GABA (γ-aminobutyric acid) slows nerve action and can bring relaxation.

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 21 Sources and Uses of Selected Amines Amphetamines are designed to mimic the action of biogenic amines and act as stimulants. They are used to treat depression, narcolepsy, and obesity. The most widely abused amphetamine is methamphetamine, commonly called “ speed. ”

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 22 Sources and Uses of Selected Amines Barbiturates are another class of drugs that are amines. These drugs are classified as sedatives and depress the activity of brain cells. An example is pentobarbital.

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 23 Basic compounds that are derived from plants and show physiological activity are known as alkaloids. These substances are usually amines. Nicotine, an alkaloid derived from tobacco leaves, acts to stimulate the nervous system. Sources and Uses of Selected Amines

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 24 Sources and Uses of Selected Amines Coffee beans and tea leaves contain caffeine, an alkaloid stimulant.

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 25 Sources and Uses of Selected Amines These drugs are classified as narcotics because they produce physical addiction, and they are strictly regulated by federal law. An example is methadone.

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Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 27 Sources and Uses of Selected Amines Another common narcotic alkaloid, cocaine, is obtained from the leaves of the coca plant.

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

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 31

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. 32

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 33 IUPAC names for amides are formed from the IUPAC names of carboxylic acids. Here are two examples. Amides: Nomenclature and Physical Properties

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 34 The common names for amides are formed from the common names of carboxylic acids. Amides: Nomenclature and Physical Properties

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 35

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 36  Polyamides are condensation polymers that contain repeating amide linkages as shown here. Polyamides: Condensation Polymers

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 37 Polyamides are either synthetic like Nylon-66 or are biological like the protein chymotrypsin. The structure of chymotrypsin is shown below. Polyamides: Condensation Polymers

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 38 The structure of synthetic Nylon-66 is shown here. Polyamides: Condensation Polymers

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 39  Urea is a simple diamide that is excreted in urine. Urea is the metabolite the body uses to excrete toxic ammonia. Urea is a white solid that melts at 133  C. It is very soluble in water. Urea

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) 40

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 41

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 42

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) 43

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 44

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 45

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. 46

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Some Amides in Health and Medicine 47

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. 48

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 49

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Hydrolysis Reactions 50

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 51

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Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 53