Aldehydes and KetonesAldehydes and Ketones

Chapter 14Chapter 14

StructureStructure Aldehydes and ketones contain a carbonyl Aldehydes and ketones contain a carbonyl

group which consists of a carbon double-bonded group which consists of a carbon double-bonded to an oxygen.to an oxygen.

In aldehydes, the carbonyl group is at the end.In aldehydes, the carbonyl group is at the end. In ketones, the carbonyl group is located within In ketones, the carbonyl group is located within

the chain.the chain.

C

O

C

H R

O

C

R R

O

Aldehyde Ketone

PropertiesProperties

Polar compoundsPolar compounds Boiling points higher than ethers and Boiling points higher than ethers and

hydrocarbons but less than alcoholshydrocarbons but less than alcohols Alkanes < Ethers < Aldehydes and Ketones < AlcoholsAlkanes < Ethers < Aldehydes and Ketones < Alcohols

Aldehydes and ketones with less than five Aldehydes and ketones with less than five carbons are soluble in water.carbons are soluble in water.

Properties Practice Problem 1Properties Practice Problem 1

Which member in each pair would have a higher Which member in each pair would have a higher boiling point?boiling point?

A.A.

B. B.

CH3COH

O

CH3CCH3

O

CH3CH2CH2CH3 CH3CH2CH

O

Properties Practice Problem 1 Properties Practice Problem 1 AnswerAnswer

Which member in each pair would have a higher Which member in each pair would have a higher boiling point?boiling point?

A.A.

B. B.

CH3COH

O

CH3CCH3

O

CH3CH2CH2CH3 CH3CH2CH

O

Properties Practice Problem 2Properties Practice Problem 2

Which member in each of the following pairs will Which member in each of the following pairs will be more water soluble?be more water soluble?

A.A.

B. B.

CH3CH2CH2CH3 CH3CH2CH

O

CH3CH2CH2CCH2CH2CH3

O

CH3CH2CH

O

Properties Practice Problem 2Properties Practice Problem 2

Which member in each of the following pairs will Which member in each of the following pairs will be more water soluble?be more water soluble?

A.A.

B. B.

CH3CH2CH2CH3 CH3CH2CH

O

CH3CH2CH2CCH2CH2CH3

O

CH3CH2CH

O

IUPAC Nomenclature of AldehydesIUPAC Nomenclature of Aldehydes

Determine the parent chain which is the Determine the parent chain which is the longest continuous chain containing the longest continuous chain containing the carbonyl group.carbonyl group.

Replace the final –e with –al.Replace the final –e with –al. Number the chain beginning with the Number the chain beginning with the

carbonyl carbon.carbonyl carbon. Number and name all substituents as Number and name all substituents as

usual.usual.

NAMING ALDEHYDES THE NAMING ALDEHYDES THE IUPAC WAYIUPAC WAY

See page 399 question 14.3:See page 399 question 14.3:

CHCH33 O O

a)a) CHCH33CHCHCHCHCHCH22-C-H-C-H

CHCH33

OO

b)b) CHCH33CH-C-HCH-C-H

ClCl

Naming Aldehydes the IUPAC Naming Aldehydes the IUPAC wayway

OO

c)c) CHCH33CHCH22CHCH22CH-C-HCH-C-H

CHCH22CHCH33

OO

d)d) CHCH33CHCHCHCH22-C-H-C-H

OHOH

Common Names for AldehydesCommon Names for Aldehydes

Formaldehyde AKA methanalFormaldehyde AKA methanal Acetaldehyde AKA ethanalAcetaldehyde AKA ethanal

Others can be found in Table 14.1 on pg. Others can be found in Table 14.1 on pg. 398398

IUPAC Nomenclature for KetonesIUPAC Nomenclature for Ketones

Very similar to naming aldehydesVery similar to naming aldehydes The –e ending is replaced with –one.The –e ending is replaced with –one. The location of the carbonyl carbon is The location of the carbonyl carbon is

indicated with a number.indicated with a number. The longest chain is numbered to give the The longest chain is numbered to give the

carbonyl carbon the lowest possible carbonyl carbon the lowest possible number.number.

Naming Ketones the IUPAC Naming Ketones the IUPAC wayway

See page 401 question 14.5See page 401 question 14.5

OO O O

a)a) CHCH33CH-C-CHCH-C-CH33 b) CHb) CH33CH-C-CHCH-C-CH33

II CH CH33

OO OO

c) CHc) CH33CH-C-CHCH-C-CH22CHCH33 d) CHd) CH33CHCHCHCH22-C-CH-C-CH33

FF CH CH22CHCH22CHCH22CHCH3

Common Nomenclature for Common Nomenclature for KetonesKetones

Propanone is also known as acetone.Propanone is also known as acetone. Name the alkyl groups that are bonded to Name the alkyl groups that are bonded to

the carbonyl carbon.the carbonyl carbon. Use these as prefixes followed by the Use these as prefixes followed by the

word ketone.word ketone. Arrange the alkyl groups alphabetically.Arrange the alkyl groups alphabetically.

KETONES- COMMON NAMESKETONES- COMMON NAMES

OO O O

a)a) CHCH33CH-C-CHCH-C-CH33 b) CHb) CH33CH-C-CHCH-C-CH33

CHCH33

OO O O

c) CHc) CH33CH-C-CHCH-C-CH22CHCH33 d) CHCHd) CHCH22-C-CH-C-CH33

CHCH22CHCH22CHCH22CHCH

HomeworkHomework

Pg. 418: Pg. 418:

# 14.25, 26, 27, 31, 33, 35, & # 14.25, 26, 27, 31, 33, 35, & 3636