Download Functional Groups - Waterford Public Schools

FUNCTIONAL GROUPS
Other Organic Functional
Groups
Alcohols
• Organic compounds with one or more hydroxyl groups, -OH
• General formula:
CnH2n+1OH
• Three classes of alcohols:
R
C
R''
H
H
OH
H
Primary,
1
R
C
OH
R'
Secondary,
2
R
C
OH
R'
Tertiary,
3
Naming of Alcohols
• The longest carbon chain containing the –OH group is chosen
• The position of the –OH group is indicated by the smallest
possible number
• Ending changes to -ol
Examples
1- Propanol
2- Propanol
2-methyl-2-propanol
5
5
2
OH
3
4
OH
Pentane
Pentane-2,4-diol
‘e’ is retained in diol
6
1
Phenols
7
• Derived from aromatic hydrocarbons
• Contain one or more –OH groups attached to an
aryl group
Ar – OH
Aryl group
Hydroxyl group
OH
OH
1
OH
8
2
Phenol

Benzene-1,2-diol 
2-hydroxyphenol
OH
1
Cl
OH
OH
1
1
2
3
4
Cl
2-chlorophenol
3-chlorophenol
4-chlorophenol
o-chlorophenol
m-chlorophenol
p-chlorophenol
o  ortho
m  meta
p  para
9
Cl
Aldehydes
• Organic compounds that contain a H-C=O group
• The C=O is called a carbonyl group
• Product of the dehydrogenation of alcohols
H
R
C
R
O
C
H
O
+
H
H
• The aldehyde group, -CHO, always occupies the terminal
position
• Therefore, no need to specify its position
• Ending changes to -al
H2
Examples
O
O
O
O
H
H
H
H
Methanal
Ethanal
AKA
Formaldehyde
H
Propanal
Benzaldehyde
Ketones
• Organic compound that contains a carbonyl group with no H
atom directly attached to it
R
C
O
'R
• Only need to specify position in carbon chain when ketone can
be in multiple positions
• Ending changes to -one
Examples
Propanone – AKA acetone
Butanone – AKA Methyl Ethyl Ketone
2-Pentanone - Note the number is
necessary because the C=O could be
on carbon 2 or carbon 3
Examples
O
4
2
O
2
3
4-methyl-2-pentanone
2-methyl-3-pentanone
Examples
3
O
O
O
2
4
2
O
Pentane-2,3-dione
Pentane-2,4-dione
Carboxylic Acids
• Organic compounds that contain a carboxyl group
O
C
Carbonyl
= Carboxyl
OH
Hydroxyl
• The carboxyl group, -COOH, always occupies the terminal
position
• No need to specify its position
• Ending changes to –oic acid
Examples
O
O
O
OH
OH
OH
H
Methanoic acid
Ethanoic acid
Propanoic acid
Butanoic acid
Examples
COOH
COOH
COOH
1
OH
1
2
3
Benzoic acid
2-hydroxybenzoic acid
3-methylbenzoic acid
Esters
• Derived from a carboxylic acid and an alcohol
O
R
C
+
O
HO
R'
H2O
H
O
R
C
O
Ester
• When naming esters:
• Carbon chain containing C=O gets suffix
• Ending changes from –oic acid to –oate
• Name of “R” group from alcohol precedes
R'
Examples
O
O
Methyl Ethanoate
spacing
Ethyl butanoate
Butyl ethanoate
Ethers
• Organic compounds that contain an oxy, -O-, group
R
O
oxy group
R
• When naming, the oxy groups are always treated as
substituents and expressed as prefixes
Examples
methane
O
ethoxy
ethoxymethane

22
Examples
O
ethane
methoxy
methoxyethane

Examples
O
phenoxy
methane
phenoxymethane

Examples
benzene
O
methoxy
methoxybenzene

Examples
1
2
3
propane
O
methoxy
2-methoxypropane

Amines
• Organic compounds that are derivatives of ammonia, NH3
H
N
H
R
Primary(1°) amine
H
NH3
N
R
Secondary(2°) amine
'R
''R
N
'R
R
Tertiary (3°) amine
Naming Primary Amines
• When the amino group is attached to a hydrocarbon family
like CC, C=C, X- and RO-, the amine group is always treated as
the principal functional group and expressed as a suffix
• Ending changes to –amine
methanamine
NH2
NH2
NH2
ethenamine (ethylenamine)
ethynamine (acetylenamine)
Naming Primary Amines
• When naming amine groups with other functional groups, the
amino group is always treated as the substituent and
expressed as a prefix, amino-
2
HO
1
NH2
2-aminoethanol
Naming Secondary and
Tertiary Amines
• Use the designation “N” to state group that is directly
attached to amine group
N-methylmethanamine
NH
N-methylethanamine
NH
Examples
N
N
N,N-dimethylethanamine
N,N-dimethylmethanamine
Aromatic Amines
NH2
NOT benzenamine
phenylamine or aniline
Examples
NH2
NH
2-methylaniline

N-methylaniline

N-phenylmethanamine
Formation of Primary Amides
• Organic compound that is derived from a carboxylic acid and an amine
O
R
C
+
H
NH2
OH
H2O
O
R
C
NH2
1° amide
N links to only ONE C
• The amide group always occupies the terminal position in a primary
amide
• No need to specify its position
• Suffix of –amide is used
Examples of Primary Amides
O
Ethanamide
NH2
Butanamide
Formation of Secondary
Amides
O
R
+
C
OH
H
H2O
NH
R'
1o amine
O
R
C
HN
R'
2° amide
N links to TWO C atoms
• When naming secondary and tertiary amides:
• Carbon chain containing C=O gets suffix, –amide
• Use the designation “N” to state R group that is directly attached to amine
group
Formation of Tertiary Amides
O
R''
O
R
+
C
H
N
H2O
R
C
N
R'
R'
OH
2o
amine
''R
3° amide
N links to THREE C atoms
Examples
O
N-methyl ethanamide
HN
NO spacing
O
N,N-dimethylethanamide
N
Nitriles
• Compounds that contain the cyano group, -CN
• If acting as the principal functional group:
• The carbon of the -CN group is counted as part of the longest
carbon chain
• The -CN group always occupies the terminal position so no need to
specify its position
• Ending changes to –nitrile
C
1
3
2
ethanenitrile
N
C
N
2-methylpropanenitrile
Nitriles
• If acting as the substituent:
• The carbon of the -CN group is NOT counted as part of the
longest carbon chain
• The prefix, cyano-, is used
N
1
HOOC
2
3
C
3-cyano-2-methylpropanoic acid
A Summary of All Organic Compounds
Alkane
Alcohol
Carboxylic acid
O
OH
OH
Alkene
Ether
Amine
NH2
O
Alkyne
C
Ketone
Amide
O
O
C
NH2
Haloalkane
Aldehyde
Amino acid
O
O
Cl
Br
H2N
H
OH