Transcript Functional Groups

Functional Groups
By Dr. Christophy
Functional Groups
• “Arrangements of atoms in an organic
compound that is capable of characteristic
chemical reactions.”
• Functional groups contain at least one
atom that is not C or H, usually O or N or a
halogen.
• R is used to represent a carbon/hydrogen
chain. R’ is used to represent a chain that
may be different on the same molecule.
Alkyl Halides
• Hydrocarbon in which a halogen is
attached to a carbon chain.
• The halogen is named as a substituent
group, just like ethyl or methyl.
• The halogen names are fluoro-, chloro-,
bromo- and iodo-
Naming Examples – Alkyl Halides
Name this structure:
Name this structure:
Cl
H3C
H2
C
C
H
Br
CH3
H3C
H2
C
C
H
H
C
CH3
Br
Click here to see the answer
Click here to see the answer
Alcohols
• An alcohol contains an “OH” group attached
to a hydrocarbon.
OH
CH
R
R'
Alcohols (cont.)
• Alcohols all have the ending “-ol”.
• A number indicates to which carbon the
functional group is attached. The alcohol gets
the lowest number possible.
• Example:
OH
CH
H3C
2-propanol
CH3
Naming Examples - Alcohols
Name this alcohol
Name this alcohol:
OH
H2
C
H3C
OH
H2
C
CH
C
H2
CH
CH3
CH3
OH
CH
H3C
CH
C
H2
CH3
Click here to see the answer
Click here to see the answer
Types of Alcohols
• If the alcohol is attached to a carbon that
is also attached to two hydrogens and one
other carbon, that is a primary alcohol.
• If the alcohol is attached to a carbon that
is also attached to one hydrogen and two
other carbons, that is a secondary alcohol.
• If the alcohol is attached to a carbon that
is also attached to no hydrogens just three
other carbons, that is a tertiary alcohol.
Types of Alcohols (cont.)
Identify the following as primary, secondary and
tertiary alcohols:
OH
H2
OH
C
CH
H3C
C
H2
H3C
CH3
H2
C
H3C
Click for the answer
CH3
OH
C
CH3
Ethers
• When the hydrogen in an alcohol is instead
replaced by a hydrocarbon group, the result is
an ether:
R
O
R'
The R groups may be the same or different
Naming Ethers
• Ethers are named by naming the
hydrocarbon on either side of the oxygen.
• The R-group names are placed in
alphabetical order.
• If the R-groups are the same, the prefix
“di” is used.
• The last word in the name is “Ether”
Naming Examples: Ether
H2
C
H3C
O
H2
C
CH3
Click here to see the name
H3C
H2
C
O
H2
C
H2
C
Click here to see the name
CH3
Ketones
• A ketone, like an alcohol, has a carbon
attached to an oxygen. This time, however, the
C and the O are connected by a double-bond.
• The C=O group is called a “carbonyl” group
O
C
R
R'
Naming Ketones
• The suffix for a ketone is “-one”
• Ketones are named the same way as any
other hydrocarbon, except the longest
chain must contain the C=O group, and
the final “e” on the end of the name is
replaced by “-one”
• Number the carbon that contains the
double-bonded “O” with the lowest number
possible.
Naming Examples - Ketones
O
H3C
H2
C
C
CH
CH3
C
H2
Click here to see the name
CH3
O
H2
C
C
H3C
CH3
CH
Click here to see the name
H2C
CH3
Aldehydes
• Aldehydes are ketones at the end of a
chain.
O
R
CH
• The ending for an aldehyde is “-al”
• Since the carbonyl group is always at
the end, there is no need for a number.
Naming Examples
O
O
H2
C
H3C
H2C
CH
Click here to see the name
H2C
CH
CH2
H3C
Click here to see the name
O
H3C
CH
Click here to see the name
Carboxylic Acids
• Carboxylic Acids are kind of a combination
of an aldehyde and an alcohol.
O
R
C
O
H
Naming Carboxylic Acids
• The ending is always “-oic acid”
• Again, no number is needed because the
group is always at the end.
Carboxylic Acid Examples
O
H
C
O
H
Click here to see the name
O
H3C
H2
C
H2
C
C
O
Click here to see the name
H
Esters
• Esters are a combination of a ketone
and an ether
• The general formula is:
O
R
C
O
R'
Naming An Ester
• Esters are just a little tricky to name.
• The name of the group AFTER the “O” is
first.
• The second word in the name is the part
that includes the carboxyl group and ends
with “oate”
Naming Examples - Ester
O
H3C
H2
C
C
O
CH3
Click here to see name
O
H3C
H2
C
H2
C
H2
C
C
O
Click here to see name
H2
C
CH3
Amines
• Amines contain a nitrogen attached to a
carbon and one or more hydrogens
• Like alcohols, amines can be primary,
secondary or tertiary.
R
R'
N
R"
Any of these R groups
could be a hydrogen
Amides
• An amide is attached to a carbon that has a
carbonyl group.
O
C
R
H
N
R'