1. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition© 2015 Pearson Education, Inc. 12.3 Aldehydes and Ketones Vanilla flavoring liquid is prepared by soaking vanilla beans in ethanol and water. Vanillin, the ingredient in vanilla beans that produces the flavor, contains an aldehyde functional group. Learning Goal Write the IUPAC and common names for aldehydes and ketones; draw the condensed structural formulas. Describe the solubility of aldehydes and ketones in water.

2. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition© 2015 Pearson Education, Inc. Aldehydes and Ketones: Carbonyl Group A carbonyl group consists of a carbon–oxygen polar double bond with two groups of atoms attached to the carbon has a very electronegative oxygen atom has two lone pair electrons on the O atom has a strong dipole with a partial positive charge on C and a partial negative charge on O

3. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition© 2015 Pearson Education, Inc. A carbonyl group in an aldehyde is attached to a carbon atom and at least one H atom a ketone is attached to two alkyl groups Aldehydes and Ketones: Carbonyl Group

4. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition© 2015 Pearson Education, Inc. Aldehyde and Ketone Structures An aldehyde group may be written as —CHO, with the double bond understood. In a ketone, the carbonyl group is bonded to two alkyl groups or aromatic rings. The keto group (C O) can sometimes be written as CO.

5. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition© 2015 Pearson Education, Inc. An aldehyde has an IUPAC name in which the e in the alkane name is changed to al has a common name for the first four aldehydes that use their common names, which end in aldehyde one carbon, formformaldehyde two carbons, acet acetaldehyde three carbons, propionpropionaldehyde four carbons, butyr butyraldehyde followed by aldehyde Naming Aldehydes

6. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition© 2015 Pearson Education, Inc. Naming Aldehydes

7. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition© 2015 Pearson Education, Inc. Guide to Naming Aldehydes

8. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition© 2015 Pearson Education, Inc. Naming Aldehydes Give the IUPAC name for the following aldehyde: SOLUTION ANALYZE Functional Group Family IUPAC Naming THE carbonyl group aldehyde change e to al and PROBLEM count the carbonyl as carbon 1

9. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition© 2015 Pearson Education, Inc. Naming Aldehydes Give the IUPAC name for the following aldehyde: STEP 1 Name the longest carbon chain by replacing the e in the alkane name with al. pentanal

10. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition© 2015 Pearson Education, Inc. Naming Aldehydes Give the IUPAC name for the following aldehyde: STEP 2 Name and number substituents by counting the carbonyl group as carbon 1. 2-methylpentanal

11. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition© 2015 Pearson Education, Inc. Chemistry Link to the Environment: Vanilla Today, much of the vanilla we use in the world is grown in Mexico, Madagascar, Réunion, Seychelles, Tahiti, Sri Lanka, Java, the Philippines, and Africa. There are many species of vanilla, but Vanilla planifolia (or V. fragrans) is considered to produce the best flavor.

12. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition© 2015 Pearson Education, Inc. Chemistry Link to the Environment: Vanilla Vanilla seeds and pods are used to flavor desserts such as custards and ice cream extract is made by chopping up vanilla beans and mixing them with a 35% ethanol–water mixture liquid that is drained from the bean residue contains the aldehyde vanillin, used for flavoring

13. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition© 2015 Pearson Education, Inc. Naming Ketones When naming the following ketones in the IUPAC system, the e in the alkane name is replaced with one with a common name, the alkyl groups attached to the carbonyl group are named alphabetically, followed by ketone

14. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition© 2015 Pearson Education, Inc. Guide to Naming Ketones

15. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition© 2015 Pearson Education, Inc. Naming Ketones Name the following ketone using the IUPAC system: SOLUTION ANALYZE Functional Family IUPAC Naming THEGroup PROBLEM carbonyl group ketonechange e to one and count from the end of the chain nearer the carbonyl group

16. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition© 2015 Pearson Education, Inc. Naming Ketones Name the following ketone using the IUPAC system: STEP 1 Name the longest carbon chain by replacing the e in the alkane name with one. pentanone

17. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition© 2015 Pearson Education, Inc. Naming Ketones Name the following ketone using the IUPAC system: STEP 2 Number the carbon chain starting from the end nearer the carbonyl group and indicate its location. 2-pentanone

18. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition© 2015 Pearson Education, Inc. Naming Ketones Name the following ketone using the IUPAC system: STEP 3 Name and number any substituents on the carbon chain. 4-methyl-2-pentanone

19. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition© 2015 Pearson Education, Inc. Aldehydes and Ketones in Water Aldehydes and ketones form hydrogen bonds with water molecules between the carbonyl oxygen and hydrogen atoms on water molecules are very soluble when they have four or fewer carbons but not soluble when they have longer hydrocarbon chains, which are nonpolar, that diminish the solubility effect of the polar carbonyl group

20. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition© 2015 Pearson Education, Inc. Aldehydes and Ketones in Water

21. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition© 2015 Pearson Education, Inc. Important Aldehydes and Ketones Acetone (propanone) is a solvent used in nail polish remover, cleaning fluids, and paint. Formaldehyde, the simplest aldehyde, is a colorless gas with a pungent odor and is used in a solution to preserve biological specimens.

22. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition© 2015 Pearson Education, Inc. Study Check Classify each as an aldehyde or ketone. O O || || A. CH 3 —CH 2 —C—CH 3 B. CH 3 —C—H CH 3 O | || C. CH 3 —C—CH 2 —C—H D. | CH 3

23. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition© 2015 Pearson Education, Inc. Solution aldehyde ketone aldehyde ketone Classify each as an aldehyde or ketone. O O || || A. CH 3 —CH 2 —C—CH 3 B. CH 3 —C—H CH 3 O | || C. CH 3 —C—CH 2 —C—H D. | CH 3

24. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition© 2015 Pearson Education, Inc. Study Check Give the IUPAC name for each of the following ketones: A. B.

25. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition© 2015 Pearson Education, Inc. Solution Give the IUPAC name for each of the following ketones: STEP 1 Name the longest carbon chain that contains the carbonyl group by replacing the e in the alkane name with one. A. hexanone B. butanone

26. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition© 2015 Pearson Education, Inc. Solution Give the IUPAC name for each of the following ketones: STEP 2 Name the carbon chain starting from the end nearer the carbonyl group and indicate its location. A. 2-hexanone B. 2-butanone

27. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition© 2015 Pearson Education, Inc. Solution Give the IUPAC name for each of the following ketones: STEP 3 Name and number any substituents on the carbon chain. A. 2-pentanone B. 4-chloro-2-butanone