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ALDEHYDES AND KETONES

IN WEEK 1, A STUDENT SHOULD BE ABLE TO:

1. Give the IUPAC name given the structure, and draw the structure given the name, of

aldehydes and ketones. Also, draw the structure given any of the following common

names: formaldehyde, acetaldehyde, benzaldehyde, acetone, acetophenone, and

benzophenone.

2. Given the starting material and reaction conditions, predict the products of reactions

giving rise to aldehydes and ketones. Important reactions include:

Oxidation of 1° and 2° alcohols

Ozonolysis of alkenes

Hydroboration of alkynes

Acid-catalyzed hydration of alkynes

3. Predict the products of the following reactions using aldehydes and ketones.

Reactions with hydrides (reducing agents such as LiAlH4 and NaBH4)

Reactions with water and alcohols (to form hemiacetals, acetals)

Reactions with derivatives of ammonia (to form oximes, semicarbazides, hydrazones,

imines, and enamines)

Reactions with thiols

Oxidation

Wolff-Kishner reduction of ketones to alkanes, and Clemmensen reduction of

benzylic ketones

4. Propose syntheses using the reactions of Objectives #2 and #3.

5. Propose mechanisms of reactions involving nucleophilic attack on the carbonyl carbon.

6. Predict structures based on 1H NMR and

13C NMR spectral data. Also, predict NMR

signals of a given compound.

IN WEEK 2, A STUDENT SHOULD ALSO BE ABLE TO:

7. Perform the objectives detailed above for these additional reactions with an emphasis on

C-C bond forming reactions in synthesis:

Friedel-Crafts acylation

Reactions with Grignard and organolithium reagents

Reactions with ylides, plus other reactions in the Wittig reaction sequence

Addition of HCN to form cyanohydrin

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To best prepare for this module, please work appropriate problems in the textbook.

A STUDENT WHO HAS MASTERED THE OBJECTIVES FOR THIS UNIT SHOULD BE

ABLE TO SOLVE THE FOLLOWING PROBLEMS AND RELATED ONES:

Problems 1-6 should be mastered for the first week of drill:

1.1 Draw each of the following compounds.

a) acetaldehyde b) acetophenone c) 2-methylcyclopentanone

1.2 Name each of the compounds shown.

2. Predict the product(s) of each of the following reactions.

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3.

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4. Propose syntheses of each of the compounds indicated, from the given starting material

and any other needed reagents.

5. Propose a mechanism for each of the following reactions, showing lone pairs, curved

arrows, and all mechanistic intermediates.

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6.1 Propose structures for each of the following compounds:

a) C9H10O2

IR: 1695 cm-1

1H NMR:

triplet, 1.3 (3H)

quartet, 4.1 (2H)

doublet, 6.9 (2H)

doublet, 7.8 (2H)

singlet, 9.9 (1H)

b) C10H12O

IR: 1710 cm-1

1H NMR:

triplet, 1.0 (3H)

quartet, 2.2 (2H)

singlet, 3.8 (2H)

multiplet, 7.2 (5H)

6.2 Predict the IR, 13

C NMR and 1H NMR spectrum of the following cinnamaldehyde

molecule.

The remainder of the problems should be mastered for the second week of drill along with

knowledge of Problems 1-6.

7.1 Predict the product(s) of each of these reactions.

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7.1

7.2 Complete these reactions.

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7.2

7.3 Propose syntheses of each of the compounds indicated.

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7.3

7.4 Propose a mechanism for this reaction, adding lone pairs where necessary.

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SOLUTIONS TO SAMPLE PROBLEMS:

1.1 a) acetaldehyde b) acetophenone c) 2-methylcyclopentanone

1.2 a) 4-methyl-2-pentanone or 4-methylpentan-2-one

b) 2-hydroxy-3,3-dimethylcycloheptanone

c) 3-chloropropanal

2. Predict the product(s), starting materials or reagents for of each of these reactions.

3. Predict the product(s) of each of these reactions.

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3. continued

4. Synthesis

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4. continued

5. Mechanisms:

6.1 Unknowns:

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6.2 Cinnamaldehyde, 3-phenyl-2-propenal or 3-phenylprop-2-enal 13

C NMR, 7 total peaks: ~180-200 ppm, 1 peak; ~100-200 ppm, 6 peaks

1H NMR, 6 total peaks: ~9-10 ppm, s, 1H; ~ 7-8 ppm, t, 1H; ~7-8 ppm, t, 2H;

~ 7-8 ppm, d, 2H; ~5-6 ppm, d, 1H; ~5-6 ppm, d, (1H)

IR: ~1680 cm-1

(C=O); ~1610 cm-1

(C=C)

7.1

7.2

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7.2 continued

7.3

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7.3 continued

7.4

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Name ________________________________________________ Drill Test 6.1 (Sample A)

Organic Chemistry 2220D Answer All Questions

1. Draw the structure of: p-nitroacetophenone 2. Give the IUPAC name of:

3. Predict the products of these reactions:

4. Propose complete mechanisms for these reactions. Include lone pairs, intermediates, and

arrows where necessary.

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4.

5. Propose syntheses for these compounds:

6. Draw the structure for a compound that is consistent with these data:

IR: 2950 cm-1

; 1750 cm-1

13

C NMR: 212, 42, 27, 18 ppm 1H NMR: 2.6 ppm, septet, 1H; 2.1 ppm, singlet, 3H; 1.1 ppm, doublet, 6H

m/z of molecular ion: 86

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Name ______________________________________________ Drill Test 6.1 (Sample B)

Organic Chemistry 2220D Answer All Questions

1. What is the IUPAC name of: 2. Draw the structure of:

2,2,2-trichloroacetaldehyde

3. Predict the products of these reactions:

4. Propose syntheses for:

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4.

5. Propose complete mechanisms for these reactions. Include all lone pairs, intermediates,

and arrows where necessary.

6. Predict the IR and 1H NMR spectra of 3-pentanone.

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Name ________________________________________________ Drill Test 6.2 (Sample A)

Organic Chemistry 2220D Answer All Questions

1. Name:

2. Draw the structure of:

a) 1,1-diiodo-3-pentanone b) 2-hydroxypropanal

3. Predict the product or products (if any) of each of the following reactions.

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4. Propose a synthesis of each of the compounds shown, from the given starting material

and any other needed reagents.

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Name ______________________________________________ Drill Test 6.2 (Sample B)

Organic Chemistry 2220D Answer All Questions

1. Which of the following compounds gives a new product on reaction with H2CrO4, and

decolorizes Br2 in CCl4?

2. Give the IUPAC name for the 3. Draw the structure of

following compound. 2,3-dimethylcyclopentanone.

4. Predict the product of each of the following reactions.

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5. Propose a synthesis of each of the compounds indicated from the given starting materials

and any other needed reagents.

6. Propose a mechanism for the reaction shown. Include all lone pairs, intermediates, and

arrows.

7. An unknown has the formula C4H6O, a strong peak in the IR spectrum near 1690 cm-1

,

with the following 1H NMR spectrum:

doublet, 2.0, 3H

multiplet, 6.1, 1H

multiplet, 6.9, 1H

doublet, 9.5, 1H