1.Chapter 21.1 and 2
Functional Groups and Classes of Organic Compounds

2. Define functional group and explain why functional groups are important.
Identifyand alcohols, alkyl halides, ethers, aldehydes, ketones, carboxylic acids, esters, and amines based on the functional group present in each
Explain the relationships between the properties and structures of compounds with various functional groups
Objectives:
3. Functional Groups
An atom or group of atoms that is responsible for the specific properties of an organic compound
Compounds that contain the same functional group can be classed together
Makes properties that are very different from those of the corresponding hydrocarbon.
4. Comparing Classes of Organic Compounds
5. Common Functional Groups
6. More Functional Groups
7. Alcohols
Organic compounds that contain one or more hydroxyl groups
General formula for a class of organic compounds
Consists of the functional group and the letter R
which stands for the rest of the molecule
General formula for alcohols
ROH
Hydroxyl group, OH,
Makes alcohols able to hydrogen-bond
makes them soluble in water
8. Uses of Alcohols
Lotions, creams, and cosmetics
usually contain an alcohol called glycerol to keep them moist
Alternative fuels
Ex: gasohol, a one-to-nine ratio of ethanol and gasoline
Simple alcohols - Ethanol
Poisonous to some extent
9. Alkyl Halides
Organic compounds in which one or more halogen atomsfluorine, chlorine, bromine, or iodine
are substituted for one or more hydrogen atoms in a hydrocarbon
General formula of an alkyl halideis
RX (where X represents any halogen).
EX:
Chlorofluorocarbons, or CFCs (implicated in ozone-layer depletion)
Teflon, a polymer made from tetrafluoroethene, C2F4
10. Ethers
organic compounds in which two hydrocarbon groups are bonded to the same atom of oxygen
General formula of an ether:
ROR
R represents a hydrocarbon group
R same or different hydrocarbon group
Not very reactive compounds
Relatively nonpolar
Uses:
Solvents
Some have pleasant odors, used in perfumes
11. Alcohol Nomenclature
Name Parent hydrocarbon:
Longest chain containing hydroxyl group
Drop e, add ol
More than one hydroxyl group
2-diol
3-triol
Number so hydroxyl group has lowest number possible
Insert number immediately beforename of parent hydrocarbon
OH
OH
C
C
C
C
C
C
C
C
1-butanol
2,2 - butandiol
OH
12. Alkyl Halide Nomenclature
Name Parent hydrocarbon
Find longest chain
Prefixes for halogens --- fluoro, bromo, chloro , iodo
If more than one, put in alphabetical order
If more than one of the same, use prefixes di, tri, tetra
Number carbon atoms
Lowest number in its name
If halogen in same position alphabetical
Br
Br
Cl
Cl
Cl
C
C
C
C
C
C
C
C
1,2 - dibromobutane
Cl
1,1,1,3 - tetrachlorobutane
13. Ether Nomenclature
Name the parent compound
The word etherwill come at the end of the name
Add names of alkyl groups
Arrange names in alphabetical order
If both are same, use prefix di
Leave spaces in the name
Space between alkyl group names and ether
C
O
C
C
C
C
C
O
C
C
C
diethyl ether
ethyl propyl ether
14. Contain the carbonyl group.
Aldehydes
organic compounds in which the carbonyl group is attached to a carbon atom at the end of a carbon-carbon chain
Ketones
organic compounds in which the carbonyl group is attached to carbon atoms within the chain
Aldehydes and Ketones
15. The general formula for an aldehyde is:
The general formula for a ketone is:
Aldehydes and ketones are often responsible for certain odors and flavors
16. Locate parent compound
Longest chain containing carbonyl group
Always number carbonyl group as 1
Change e to al
All other rules apply (ex: number from side closest to the carbonyl group
Aldehyde Nomenclature
C
O
C
O
C
O
C
C
C
C
C
C
C
C
C
C
C
C
C
propanal
3,3 - dimethylpropanal
2 ethyl pentanal
17. Locate Parent compound
Must contain carbonyl group and it must contain the lowest number
Change e to one
All other rules apply
Ketone Nomenclature
O
O
C
O
C
C
C
C
C
C
C
C
C
C
C
C
C
propanone
2 - pentanone
C
2,2 - dimethyl 3 - pentanone
18. Amines
Amines
Organic compounds that can be considered to be derivatives of ammonia, NH3
General formula of an amine :
Amines are common in nature.
Often form during the breakdown of proteins in animal cells
The unshared electron pair on the nitrogen makes amines act as weak bases in aqueous solutions:
19. Amine Nomenclature
Name the parent compound
End will be amine
Add alkyl groups
Alphabetical order
Use prefixes, di-, tri-
H
H
C
C
H
N
C
C
N
C
C
C
N
methylamine
ethylmethylamine
trimethylamine
PRIMARY AMINE
SECONDARY AMINE
TERTIARY AMINE
20. Carboxylic Acids
organic compounds that contain the carboxyl functional group
General formula:
Like inorganic acids
Carboxylic acids react to lose a hydrogen ion and become a negatively charged ion in water
21. Examples
acetic acid (the weak acid in vinegar)
citric acid
benzoic, propanoic, and sorbic acids (used as preservatives)
Much weaker than many
inorganic acids
22. Carboxylic Acids Found in Plants and Animals
23. Carboxylic Acid Nomenclature
Name Parent Compound
Longest chain contains carboxyl group
Drop e, add oic acid
More than one, use full name of parent compound (dont drop -e )
-dioic acid = 2, -trioc acid = 3
O
O
O
O
C
C
C
OH
C
C
OH
C
C
C
OH
C
HO
propanoic acid
C
ethanedioic acid
3 - methylbutanoic acid
24. Esters
organic compounds that have carboxylic acid groups in which the hydrogen of the hydroxyl group has been replaced by an alkyl group
General formula:
considered derivatives of carboxylic acids because of their structural similarity to carboxylic acids
Like aldehydes and ketones, esters are responsible for many common odors and flavors
25. Common Odors and Flavors of Esters
26. Esters Nomenclature
Name parent compound
Name carboxylic acid
Change oic acid to oate
Add the name of the alkyl group
This will be the front of the name
O
O
C
O
C
C
C
C
C
O
C
C
C
C
Methyl butanoate
ethyl propanoate