Chapter 12 Organic Compounds with Oxygen and Sulfur

1. Chapter 12 Organic Compounds with Oxygen and Sulfur 12.4 Aldehydes and Ketones

2. Carbonyl Group in Aldehydes and Ketones A carbonyl group • consists of a carbon-oxygen polar double bond • has a very electronegative oxygen atom • has two lone pair electrons on the O atom • has partial positive charge on C and partial negative charge on O

3. Carbonyl Group in Aldehydes and Ketones A carbonyl group • in analdehyde is attached to at least one H atom • in a ketone is attached to two carbon groups

4. Naming Aldehydes 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 the following prefixes: 1 carbon, form 2 carbons, acet 3 carbons, propion 4 carbons butyr followed by aldehyde

5. Naming Aldehydes

6. Naming Aldehydes

7. Naming Aldehydes Give the IUPAC name for the following aldehydes: O || CH3CH2CH2CHCH | CH3

8. Naming Aldehydes Step 1 Name the longest carbon chain containing the carbonyl group by replacing the e in the alkane namewith al. O || CH3CH2CH2CHCH | CH3 pentanal benzaldehyde

9. Naming Aldehydes Step 2 Name and number substituents by counting the carbonyl group as carbon 1. O || CH3CH2CH2CHCH | CH3 2-methylpentanal 3,4-dichlorobenzaldehyde

10. Aldehydes in Flavorings Several naturally occurring aldehydes are used as flavorings for foods and fragrances.

11. 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 OO CH3CCH3 CH3CCH2CH3 propanone 2-butanone (dimethyl ketone) (ethyl methyl ketone)

12. Naming Ketones

13. Naming Ketones Name the following ketones using the IUPAC system. O || CH3CH2CHCH2CCH3 | CH3

14. Naming Ketones Step 1 Name the longest carbon chain that contains the carbonyl group by replacing the e in thealkane name with one. O || CH3CH2CHCH2CCH3 | CH3 hexanone pentanone

15. Naming Ketones Step 2 Number the carbon chain starting from the end nearer the carbonyl group and indicate its location. O || CH3CH2CHCH2CCH3 | CH3 2-hexanone pentanone

16. Naming Ketones Step 3 Name and number any substituents on the carbon chain. O || CH3CH2CHCH2CCH3 | CH3 4-methyl-2-hexanone 2,3-dimethylcylcopentanone

17. Ketones in Common Use Acetone (propanone) is a solvent used in nail polish remover. Butanedione is the butter flavoring used in margarine.

18. Learning Check Classify each as an aldehyde or ketone. O O || || A. CH3—CH2—C—CH3 B. CH3—C—H CH3 O | || C. CH3—C—CH2—C—H D. | CH3

19. Solution Classify each as an aldehyde or ketone. O O || || A. CH3—CH2—C—CH3 B. CH3—C—H CH3 O | || C. CH3—C—CH2—C—H D. | CH3 aldehyde ketone ketone aldehyde

20. Learning Check Classify each as an aldehyde, ketone, alcohol, or ether. O A. CH3CH2CCH3 B. CH3OCH3 CH3 O OH C. CH3CCH2CH D. CH3CHCH3 CH3

21. Solution Classify each as an aldehyde, ketone, alcohol, or ether. O A. CH3CH2CCH3 B. CH3OCH3 CH3 O OH C. CH3CCH2CH D. CH3CHCH3 CH3 ketone ether aldehyde alcohol

22. Learning Check Give the IUPAC name for each of the following ketones. O A. CH3CH2CH2CH2CCH3 O B. ClCH2CH2CCH3

23. 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. O A. CH3CH2CH2CH2CCH3pentanone O B. ClCH2CH2CCH3butanone

24. 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. O A. CH3CH2CH2CH2CCH3 2-pentanone O B. ClCH2CH2CCH3 2-butanone

25. Solution Give the IUPAC name for each of the following ketones. Step 3Name and number any substituents on the carbon chain. O A. CH3CH2CH2CH2CCH3 2-pentanone O B. ClCH2CH2CCH34-chloro-2-butanone

26. Learning Check Give the IUPAC name for the following aldehyde compounds. O || A. CH3—CH2—CH2—C—H CH3 O | || B. CH3—C—CH2—C—H | CH3

27. Solution Give the IUPAC name for the following aldehyde compounds. Step 1 Name the longest carbon chain containing the carbonyl group by replacing the e in the alkane name with al. O || A. CH3—CH2—CH2—C—H butanal CH3 O | || B. CH3—C—CH2—C—H butanal | CH3

28. Solution Give the IUPAC name for the following aldehyde compounds. Step 2 Name and number substituents by counting the carbonyl group as carbon 1. O || A. CH3—CH2—CH2—C—H butanal CH3 O | || B. CH3—C—CH2—C—H 3,3-dimethylbutanal | CH3

29. Learning Check Draw the structural formulas for each: A. 4-methylpentanal B. 2,3-dichloropropanal C. 3-methyl-2-butanone

30. Solution Draw the structural formulas for each: CH3 O A. 4-methylpentanal CH3CHCH2CH2CH Cl O B. 2,3-dichloropropanal ClCH2CHCH CH3O C. 3-methyl-2-butanone CH3CHCCH3