Timberlake LesturePLUS 1999 1

Chapter 12Alcohols, Phenols, Ethers, Aldehydes, and Ketones

Oxidation and Reduction

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Classification of Alcohols

Primary (1º) Secondary (2º ) Tertiary (3º)

H CH3 CH3

CH3-C-OH CH3-C-OH CH3-C-OH

H H CH3

1 CH3 2 CH3 3 CH3

attached attached attachedto C-OH to C-OH to C-OH

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Learning Check Ox-Red 1

Classify the following as 1º, 2º, or 3º alcohols: OH

A. CH3CH2CH2OH B. CH3-CH-CH2CH3

C. D. OH

CH3-C-CH2CH3

CH3

OH

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Solution Ox-Red 1

Classify the following as 1º, 2º, or 3º alcohols: OH

A. CH3CH2CH2OH 1º B. CH3-CH-CH2CH3 2º

C. 2º D. OH 3º

CH3-C-CH2CH3

CH3

OH

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Oxidation

Is a gain of oxygen (O)

or

A loss of hydrogen (H)

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Alcohols

1°alcohols are oxidized to aldehydes and 2° alcohols are oxidized to ketones

Alcohols 1° 2°

aldehydes ketones

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Oxidation of Alcohols

[O]

Primary alcohol aldehyde

OH O [O]

CH3-C-H CH3-C-H

H

Ethanol Ethanal

(ethyl alcohol) (acetaldehyde)

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Oxidation of Alcohols

[O]

Secondary alcohol ketone

OH O [O]

CH3-C-CH3 CH3-C-CH3

2-Propanol 2-propanone (isopropyl alcohol) (dimethyl ketone,

“acetone”)

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Oxidation of Alcohols

[O]

Tertiary alcohols no reaction

OH [O]

CH3-C-CH3 no product

CH3 no H on the C-OH to oxidize

2-Methyl-2-propanol

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Oxidation of Ethanol in the Body

Enzymes in the liver oxidize ethanolAldehyde product impairs coordinationBlood alcohol over 0.4% can be fatal.

O O

[O] [O]

CH3CH2OH CH3CH CH3COH 2CO2 + H2O

ethyl alcohol acetaldhyde acetic acid

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Learning Check Ox-Red 3

Select the product for the reaction of CH3CH2CH2OH in the following conditions:

O

1) CH3CH=CH2 2) CO2 + H2O 3) CH3CH2CH

A. H+, heat _________

B. [O] _________

C. O2, heat _________

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Solution Ox-Red 3

Select the product for the reaction of CH3CH2CH2OH in the following conditions:

A. H+, heat 1) CH3CH=CH2

O

B. [O] 3) CH3CH2CH

C. O2, heat 2) CO2 + H2O

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Learning Check Ox-Red 4

Write the structure of the following:

A. 3-pentanol

B. Dimethyl ether

C. 3-methylcyclobutanol

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Solution Ox-Red 4

Write the structure of the following:

OH

|

A. 3-pentanol CH3CH2CHCH2CH3

B. Dimethyl ether CH3-O-CH3

C. 3-methylcyclobutanolOH

CH3

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Reduction

Is a loss of oxygen (O)

or

gain of hydrogen (H)

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Reduction

Aldehydes are reduced to 1° alcohols and ketones are reduced to 2° alcohols

Alcohols

1° 2° aldehydes ketones