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 1

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 2

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. 3

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) 4

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) 5

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 6

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 7

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) 8

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 9

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 10

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. 11

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Some Amides in Health and Medicine 12

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. 13

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 14

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Hydrolysis Reactions 15

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. 16

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 17

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Concept Map: Carboxylic Acids, Esters, Amines, and Amides 18