Download Chapter 10, section 10.5

Chapter 10 Introduction to Organic
Chemistry: Alkanes
10.5
Functional Groups
Copyright © 2005 by Pearson Education, Inc.
Publishing as Benjamin Cummings
1
Elements in Organic Compounds
In organic molecules,
carbon atoms bond
• with four bonds.
• mostly with H and
other C atoms.
• sometimes to O, N,
S,
• sometimes to
halogens F, Cl, and
Br.
2
Functional Groups
Functional groups are
• a characteristic feature of organic molecules that
behave in a predictable way.
• composed of an atom or group of atoms.
• groups that replace a hydrogen atom in the
corresponding alkane.
• a way to classify families of organic compounds.
3
Alkenes and Alkynes
Alkenes contain a double
bond between adjacent
carbon atoms.
Alkynes contain a triple
bond.
Copyright © 2005 by Pearson Education, Inc.
Publishing as Benjamin Cummings
4
Alcohols and Ethers
An alcohol contains the
hydroxyl (-OH) functional
group.
In an ether, an oxygen
atom is bonded to two
carbon atoms.
–C–O–C– .
R’–O–R or R–O–R
R=alkyl group and
R’=different alkyl group
Copyright © 2005 by Pearson Education, Inc.
Publishing as Benjamin Cummings
5
Aldehydes and Ketones
An aldehyde contains a
carbonyl group (C=O),
which is a carbon atom
with a double bond to an
oxygen atom.
In a ketone, the carbon of
the carbonyl group is
attached to two other
carbon atoms.
Copyright © 2005 by Pearson Education, Inc.
Publishing as Benjamin Cummings
6
Carboxylic Acids and Esters
Carboxylic acids contain the
carboxyl group, which is a
carbonyl group attached to a
hydroxyl group.
O
║
— C—OH
An ester contains the
carboxyl group between
carbon atoms.
Copyright © 2005 by Pearson Education, Inc.
Publishing as Benjamin Cummings
7
Amines and Amides
In amines, the functional
group is a nitrogen atom.
|
—N —
In amides, the hydroxyl
group of a carboxylic acid
is replaced by a nitrogen
group.
Copyright © 2005 by Pearson Education, Inc.
Publishing as Benjamin Cummings
8
Functional Groups
Copyright © 2005 by
Pearson Education, Inc.
Publishing as Benjamin
Cummings
9
Learning Check
Classify each of the following as: alcohol, ether,
aldehyde, ketone, carboxylic acid, ester, amine or
amide.
1) CH3─CH2─CH2─OH
2) CH3─O─CH2─CH3
3) CH3─CH2─NH2
O
║
4) CH3─C─OH
O
║
5) CH3─C─O─CH3
10
Solution
1) CH3─CH2─CH2─OH
2) CH3─O─CH2─CH3
alcohol
ether
3) CH3─CH2─NH2
amine
O
║
4) CH3─C─OH
carboxylic acid
O
║
5) CH3─C─O─CH3
ester
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