Chapter 12 Reactions of Aldehydes and Ketones More

Chapter 12 Reactions of Aldehydes and Ketones More Reactions of Carboxylic Acid Derivatives Paula Yurkanis Bruice University of California, Santa Barbara © 2016 Pearson Education, Inc.

Contents of Chapter 12 n n n Structure of Aldehydes and Ketones Naming Adehydes and Ketones Reactivity with Nucleophiles Hydration of Aldehydes and Ketones Acetals and Ketals Skip Grignard Reagents, Hydride Reductions, Reactions With Amines, Conjugate Additions, and Biological Reactions Chapter 12 2

Structure of Aldehydes and Ketones or An aldehyde A ketone Chapter 12 3

Nomenclature of Aldehydes and Ketones Ø IUPAC Nomenclature of Aldehydes • • • Select as the parent compound the longest chain of carbon atoms that contains the functional group. For aldehydes, change the suffix –e of the parent name to –al. Aldehyde carbon is carbon 1. Chapter 12 4

Nomenclature of Aldehydes Chapter 12 5

Nomenclature of Aldehydes and Ketones Ø IUPAC Nomenclature of Ketones • • • Select as the parent compound the longest chain of carbon atoms that contains the functional group. For ketones, change the suffix –e of the parent name to –one. Number the chain so that the ketone group gets the lowest number. Chapter 12 6

Nomenclature of Ketones Chapter 12 7

Nomenclature of Ketones Note: The IUPAC system retains some common names such as acetone and acetophenone. Chapter 12 8

Common Names The common name for an aldehyde is derived from the common name of the corresponding carboxylic acid by changing the suffix –ic acid to –aldehyde. Chapter 12 9

Common Names Common names for ketones are derived by naming the two alkyl or aryl groups attached to the carbonyl group, followed by the word ketone. Chapter 12 10

Reactions of Aldehydes and Ketones Ø Nucleophilic Addition The more sterically-hindered the area around the carbonyl carbon is the less reactive the aldehyde or ketone is with nucleophiles Chapter 12 11

Reactions of Aldehydes and Ketones Ø Addition of Water • Aldehydes • Ketones Chapter 12 12

Formation of Acetals and Ketals Ø Addition of one molecule of alcohol to an aldehyde forms a hemiacetal: a hemiacetal Chapter 12 13

Formation of Acetals and Ketals Ø Ø Hemiacetals and hemiketals react further with alcohols to form acetals and ketals. These reactions are acid catalyzed. a hemiacetal 1, 1 -dimethoxyethane (a dimethyl acetal) Chapter 12 14

Formation of Acetals and Ketals a hemiketal 2, 2 -diethoxypropane (a diethyl ketal) Chapter 12 15

Oxidation of Aldehydes and Ketones Oxidizing agents commonly used to oxidize aldehydes to carboxylic acids are potassium permanganate and chromic acid Chapter 12 16