Title: Systematic Nomenclature
1Systematic Nomenclature
23.1 Nomenclature of Hydrocarbons 23.2 Nomenclatur
e of the Derivatives of Hydrocarbons 23.3 Nomencl
ature of the Derivatives of Aromatic Hydrocarbons
2Nomenclature
- Means naming of compounds
- The formal system of nomenclature is proposed by
International Union of Pure and Applies Chemistry
(IUPAC) - Fundamental principleEach different compound
should have a different name
3Nomenclature of Hydrocarbons
423.1 Nomenclature of Hydrocarbons (SB p.52)
Nomenclature of Hydrocarbons
- 4 groups
- Straight-chain acyclic hydrocarbons
- Branched-chain acyclic hydrocarbons
- Cyclic hydrocarbons
- Aromatic hydrocarbons
523.1 Nomenclature of Hydrocarbons (SB p.53)
Straight-Chain Acyclic Hydrocarbons
1. The naming of organic compounds is based on
the parent hydrocarbon they derived from
623.1 Nomenclature of Hydrocarbons (SB p.53)
Straight-Chain Acyclic Hydrocarbons
2. (a) The suffix -ane is used for
saturated hydrocarbons
723.1 Nomenclature of Hydrocarbons (SB p.53)
Straight-Chain Acyclic Hydrocarbons
(b) The suffix -ene is used for unsaturated
hydrocarbons with a double bond e.g. CH2
CH2 ethene CH3CH CH2 propene
823.1 Nomenclature of Hydrocarbons (SB p.53)
Straight-Chain Acyclic Hydrocarbons
(c) The suffix -yne is used for unsaturated
hydrocarbons with a triple bond e.g. CH ?
CH ethyne CH3CH ? CH propyne
923.1 Nomenclature of Hydrocarbons (SB p.54)
Straight-Chain Acyclic Hydrocarbons
3. The lowest possible number is assigned to the
carbon atoms of the multiple bond
The number is written before the suffix to
indicate the position of the carbon atom of the
multiple bond e.g. CH3CH2CH CH2 but-1-ene
(not
but-3-ene) CH3C ? CCH2CH3 pent-2-yne
(not pent-3-yne)
1023.1 Nomenclature of Hydrocarbons (SB p.54)
Straight-Chain Acyclic Hydrocarbons
- If a compound contains more than one double or
triple bond, the prefixes like di-, tri-, are
used to indicate its number of occurrence - An a is added to the corresponding stem name
- e.g. CH3CH2CH CHCH CH2
hexa-1,3-diene
1123.1 Nomenclature of Hydrocarbons (SB p.54)
Straight-Chain Acyclic Hydrocarbons
5. The geometrical isomers of an alkene are
specified by the word of cis- or trans-
before their names e.g.
1223.1 Nomenclature of Hydrocarbons (SB p.54)
Branched-Chain Acyclic Hydrocarbons
- Selecting and naming the parent hydrocarbon
- (a) For saturated hydrocarbons, the longest
possible straight chain is the parent chain, the
remaining are treated as branched chains
1323.1 Nomenclature of Hydrocarbons (SB p.54)
Branched-Chain Acyclic Hydrocarbons
e.g.
1423.1 Nomenclature of Hydrocarbons (SB p.55)
Branched-Chain Acyclic Hydrocarbons
(b) For unsaturated hydrocarbons, the longest
possible straight chain which contains the
maximum number of multiple bonds is chosen as the
parent chain
1523.1 Nomenclature of Hydrocarbons (SB p.55)
Branched-Chain Acyclic Hydrocarbons
(c) The parent hydrocarbon is named as described
in the naming of straight-chain acyclic
hydrocarbons
1623.1 Nomenclature of Hydrocarbons (SB p.55)
Branched-Chain Acyclic Hydrocarbons
- Naming branched chains
- (a) The number of carbon atoms in a branched
chain is indicated by the stem names
1723.1 Nomenclature of Hydrocarbons (SB p.55)
Branched-Chain Acyclic Hydrocarbons
- The suffix -yl is added to the corresponding
stem names for branched chains containing only
single bonds - e.g. CH3 ? Methyl
- CH3CH2 ? Ethyl
- CH3CH2CH2 ? Propyl
1823.1 Nomenclature of Hydrocarbons (SB p.55)
Branched-Chain Acyclic Hydrocarbons
- Numbering carbon atoms in the parent hydrocarbon
- (a) For saturated hydrocarbons, the parent
hydrocarbon is numbered beginning with the end
of the chain nearer the branched chain
1923.1 Nomenclature of Hydrocarbons (SB p.55)
Branched-Chain Acyclic Hydrocarbons
e.g.
2023.1 Nomenclature of Hydrocarbons (SB p.55)
Branched-Chain Acyclic Hydrocarbons
e.g.
2123.1 Nomenclature of Hydrocarbons (SB p.55)
Branched-Chain Acyclic Hydrocarbons
- For unsaturated hydrocarbons, the parent
hydrocarbon is numbered so as to include both
carbon atoms of the double or triple bond - The numbering begins with the end of the chain
neared the double or triple bond
2223.1 Nomenclature of Hydrocarbons (SB p.55)
Branched-Chain Acyclic Hydrocarbons
e.g.
2323.1 Nomenclature of Hydrocarbons (SB p.55)
Branched-Chain Acyclic Hydrocarbons
e.g.
2423.1 Nomenclature of Hydrocarbons (SB p.56)
Branched-Chain Acyclic Hydrocarbons
- Use the numbers to designate the position of the
branched chains - The parent name is placed last, and the branched
chain, preceded by the number designating its
position on the parent chain, is placed first
2523.1 Nomenclature of Hydrocarbons (SB p.56)
Branched-Chain Acyclic Hydrocarbons
e.g.
2623.1 Nomenclature of Hydrocarbons (SB p.56)
Branched-Chain Acyclic Hydrocarbons
- When two or more branched chains are present, a
number corresponding to its position on the
parent hydrocarbon is given to each branched
chain so as to give the lowest possible numbers
to the branched chains - The branched chains are listed alphabetically
(i.e. ethyl before methyl) - Multiplying prefixes such as di and tri are
ignored when deciding the alphabetical order
2723.1 Nomenclature of Hydrocarbons (SB p.56)
Branched-Chain Acyclic Hydrocarbons
e.g.
2823.1 Nomenclature of Hydrocarbons (SB p.56)
Branched-Chain Acyclic Hydrocarbons
e.g.
2923.1 Nomenclature of Hydrocarbons (SB p.56)
Branched-Chain Acyclic Hydrocarbons
6. When two branched chains are present on the
same carbon atom, use that number twice
3023.1 Nomenclature of Hydrocarbons (SB p.57)
Branched-Chain Acyclic Hydrocarbons
- When two or more branched chains are identical,
indicate this by the use of the prefixes di,
tri, tetra etc. - Commas are used to separate numbers from each
other
3123.1 Nomenclature of Hydrocarbons (SB p.57)
Branched-Chain Acyclic Hydrocarbons
e.g.
3223.1 Nomenclature of Hydrocarbons (SB p.57)
Cyclic Hydrocarbons
Simple cyclic hydrocarbons are named by adding
the prefix cyclo- to the names of their
corresponding acyclic counterparts
3323.1 Nomenclature of Hydrocarbons (SB p.57)
Cyclic Hydrocarbons
e.g.
3423.1 Nomenclature of Hydrocarbons (SB p.57)
Aromatic Hydrocarbons
1. Some aromatic hydrocarbons have specific names
3523.1 Nomenclature of Hydrocarbons (SB p.57)
Aromatic Hydrocarbons
- For substituted benzenes, the benzene ring is
numbered so as to give the lowest possible
numbers to the substituents - When more than two substituents are present and
the substituents are different, list them in
alphabetical order - The names of the substituents together with the
numbers indicating their positions are added
before the word benzene
3623.1 Nomenclature of Hydrocarbons (SB p.57)
Aromatic Hydrocarbons
e.g.
3723.1 Nomenclature of Hydrocarbons (SB p.57)
Aromatic Hydrocarbons
e.g.
3823.1 Nomenclature of Hydrocarbons (SB p.57)
39Nomenclature of the Derivatives of Hydrocarbons
4023.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.59)
Nomenclature of Compounds with One Type of
Functional Group
- 2 groups
- Compounds with functional groups that must be
designated as prefixes - Compounds with functional groups that may be
expressed as prefixes or suffixes
4123.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.60)
Compounds with Functional Groups that Must be
Designated as Prefixes
4223.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.60)
Compounds with Functional Groups that Must be
Designated as Prefixes
- Whether the carbon chains are saturated or
unsaturated, straight or branched, they are named
and numbered in the usual way - Numbers are assigned to functional groups in the
same way as the alkyl substituents
4323.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.60)
Compounds with Functional Groups that Must be
Designated as Prefixes
e.g.
4423.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.60)
Compounds with Functional Groups that Must be
Designated as Prefixes
- When the parent chain has both alkyl groups and
other substituents, the chain is numbered from
the end nearest to the first substituent,
regardless of what substituents are - All the prefixes are then arranged in
alphabetical order
4523.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.60)
Compounds with Functional Groups that Must be
Designated as Prefixes
e.g.
4623.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.61)
Compounds with Functional Groups that Must be
Designated as Prefixes
3. When two or more substituents are identical,
indicate this by the use of the prefixes di,
tri, tetra etc.
4723.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.61)
Compounds with Functional Groups that Must be
Designated as Prefixes
e.g.
4823.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.61)
Compounds with Functional Groups that May be
Designated as Prefixes or Suffixes
Suffix of compounds with one functional group
which may be expressed as prefixes or suffixes
4923.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.61)
Compounds with Functional Groups that May be
Designated as Prefixes or Suffixes
Suffix of compounds with one functional group
which may be expressed as prefixes or suffixes
5023.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.61)
Compounds with Functional Groups that May be
Designated as Prefixes or Suffixes
Suffix of compounds with one functional group
which may be expressed as prefixes or suffixes
5123.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.61)
Compounds with Functional Groups that May be
Designated as Prefixes or Suffixes
1. Principal functional group is the functional
group expressed as a suffix and has priority over
unsaturated centres 2. Parent carbon chain is
chosen to include the longest possible carbon
chain and maximum number of principal functional
groups
5223.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.61)
Compounds with Functional Groups that May be
Designated as Prefixes or Suffixes
- 3. The carbon chain is numbered to give the
principal functional group the lower number - The position of the principal functional group is
indicated by using this number - The positions of other substituents are
indicated by using the numbers corresponding to
their positions along the parent carbon chain
5323.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.62)
Compounds with Functional Groups that May be
Designated as Prefixes or Suffixes
(a) Alcohols (ending -ol)
5423.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.62)
(a) Alcohols (ending -ol)
5523.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.62)
(b) Aldehydes (ending -al) and ketones (ending
-one)
5623.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.62)
(b) Aldehydes (ending -al) and ketones (ending
-one)
e.g.
5723.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.63)
(c) Carboxylic acids (ending -oic acid)
5823.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.63)
(d) Acyl chlorides (ending -oyl chloride)
5923.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.63)
(e) Amides (ending -amide)
Alkyl groups on the nitrogen atom of amides are
named as substituents and the named substituent
is preceded by N- or N, N-
6023.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.63)
(e) Amides (ending -amide)
e.g.
6123.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.63)
(f) Esters (ending -oate)
The name of an ester is derived from the names of
the alcohol (with the ending yl) and the
carboxylic acid (with the ending -oate) forming
the ester The portion of the name derived from
the alcohol comes first, and then the carboxylic
acid
6223.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.63)
(f) Esters (ending -oate)
e.g.
6323.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.64)
6423.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.65)
Nomenclature of Compounds with More Than One Type
of Functional Group
1. Only one of the functional groups can be
designated as the ending of the name. This
functional group is the principal functional group
6523.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.65)
Prefixes and suffixes for some common functional
groups (in decreasing order of priority)
6623.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.65)
Prefixes and suffixes for some common functional
groups (in decreasing order of priority)
6723.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.66)
Nomenclature of Compounds with More Than One Type
of Functional Group
- The principal functional group has priority in
the selection of the longest possible carbon
chain and the choice of the lowest number - All other groups are designated as prefixes and
listed in alphabetical order
6823.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.66)
(a)
6923.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.66)
(a)
7023.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.66)
(a)
Substituents named as prefixes in alphabetical
order ?Cl (4-chloro)
?CH3 (4-methyl)
The name of the compound is 4-chloro-4-methylpent
anal.
7123.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.66)
(b)
7223.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.67)
(b)
7323.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.67)
(b)
Substituents named as prefixes in alphabetical
order ?Br (2-bromo)
?CH3 (3-methyl)
The name of the compound is 2-bromo-3-methylbut-2
-enoic acid.
7423.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.67)
(c)
7523.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.67)
(c)
7623.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.67)
(c)
Substituents named as prefixes in alphabetical
order ?Cl (3-chloro)
?I (2-iodo)
The name of the compound is 3-chloro-2-iodobutana
mide.
7723.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.67)
(d)
7823.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.67)
(d)
7923.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.67)
(d)
Substituents named as prefixes in alphabetical
order ?Cl (3,4-dichloro)
?OH (5-hydroxy) ?CH3 (4-methyl)
The name of the compound is 3,4-dichloro-5-hydrox
y-4-methylpentan-2-one.
8023.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.68)
(e)
8123.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.68)
(e)
8223.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.68)
(e)
The name of the compound is 4-amino-2-phenylhexan
al.
8323.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.69)
84Nomenclature of the Derivatives of Aromatic
Hydrocarbons
8523.3 Nomenclature of the Derivatives of Aromatic
Hydrocarbons (SB p.70)
Monosubstituted Aromatic Hydrocarbons
1. For certain monosubstituted aromatic
hydrocarbons, they are named by adding the names
of the substituents as prefixes to the name of
the aromatic hydrocarbon
8623.3 Nomenclature of the Derivatives of Aromatic
Hydrocarbons (SB p.70)
Monosubstituted Aromatic Hydrocarbons
e.g.
8723.3 Nomenclature of the Derivatives of Aromatic
Hydrocarbons (SB p.70)
Monosubstituted Aromatic Hydrocarbons
2. For other monosubstituted aromatic
hydrocarbons, the substituent and the benzene
ring taken together may form a new parent name
8823.3 Nomenclature of the Derivatives of Aromatic
Hydrocarbons (SB p.70)
Monosubstituted Aromatic Hydrocarbons
e.g.
8923.3 Nomenclature of the Derivatives of Aromatic
Hydrocarbons (SB p.70)
Monosubstituted Aromatic Hydrocarbons
e.g.
9023.3 Nomenclature of the Derivatives of Aromatic
Hydrocarbons (SB p.71)
Polysubstituted Aromatic Hydrocarbons
- When two or more substituents are identical,
indicate this by the use of the prefixes di-,
tri-, tetra- etc. - The benzene ring is numbered so as to give the
lowest possible numbers to the substituents
9123.3 Nomenclature of the Derivatives of Aromatic
Hydrocarbons (SB p.71)
Polysubstituted Aromatic Hydrocarbons
e.g.
9223.3 Nomenclature of the Derivatives of Aromatic
Hydrocarbons (SB p.71)
Polysubstituted Aromatic Hydrocarbons
2. When the substituents are different, they are
listed in alphabetical order
9323.3 Nomenclature of the Derivatives of Aromatic
Hydrocarbons (SB p.71)
Polysubstituted Aromatic Hydrocarbons
- When a substituent is one that when taken
together with the benzene ring gives a new parent
name - ? that substituent is assumed to be in position
1 and the new parent name is used
9423.3 Nomenclature of the Derivatives of Aromatic
Hydrocarbons (SB p.71)
Polysubstituted Aromatic Hydrocarbons
e.g.
9523.3 Nomenclature of the Derivatives of Aromatic
Hydrocarbons (SB p.72)
96The END
9723.1 Nomenclature of Hydrocarbons (SB p.58)
Example 23-1
Give the structural formula for each of the
following compounds (a) 2-Methylbutane (b)
2,2,3-Trimethylpentane (c) 3-Ethyl-2-methylhexane
Answer
9823.1 Nomenclature of Hydrocarbons (SB p.58)
Example 23-1
Give the structural formula for each of the
following compounds (d) 3-Methylbut-1-ene (e)
2-Propylpent-1-ene
Answer
9923.1 Nomenclature of Hydrocarbons (SB p.58)
Back
Example 23-1
Give the structural formula for each of the
following compounds (f) 3-Ethylhex-1-yne (g)
1,2-Dimethylbenzene (h) Cyclopentane
Answer
10023.1 Nomenclature of Hydrocarbons (SB p.59)
Check Point 23-1
- Give the IUPAC name for each of the following
compounds - (b)
Answer
- Dimethylpropane
- 2,4-Dimethylhex-2-ene
10123.1 Nomenclature of Hydrocarbons (SB p.59)
Check Point 23-1
Give the IUPAC name for each of the following
compounds (c) (d)
Answer
- 3-Methylpent-1-yne
- 1-Methylcyclohexene
10223.1 Nomenclature of Hydrocarbons (SB p.59)
Back
Check Point 23-1
Give the IUPAC name for each of the following
compounds (e)
(e) Ethylbenzene
Answer
10323.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.64)
Example 23-2A
Give the structural formula for each of the
following compounds (a) 2-Methylhexane (b)
4-Methylheptan-2-ol
Answer
10423.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.64)
Example 23-2A
Give the structural formula for each of the
following compounds (c) Pentan-2-one (d)
5-Methylhexanoic acid
Answer
10523.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.64)
Back
Example 23-2A
Give the structural formula for each of the
following compounds (e) Methyl
2,2-dimethylpentanoate (f) N-ethyl-N-propylethanam
ide
Answer
10623.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.64)
Check Point 23-2A
Give the IUPAC name for each of the following
compounds (a) (b)
- 3,4-Dimethylpentanoic acid
- Pentan-2-ol
Answer
10723.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.64)
Check Point 23-2A
Back
Give the IUPAC name for each of the following
compounds (c) (d)
(c) 3,4-Dimethylhexanal (d) N,N-Dimethylpropanamid
e
Answer
10823.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.69)
Example 23-2B
Give the structural formula for each of the
following compounds (a) 3-Oxobutanoic acid (b)
5-Hydroxypentanal
Answer
10923.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.69)
Back
Example 23-2B
Give the structural formula for each of the
following compounds (c) 2-Hydroxy-4-oxohexanal (d
) 1,8-Dihydroxyoctan-3-one
Answer
11023.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.69)
Check Point 23-2B
Give the IUPAC name for each of the following
compounds (a) (b)
- 3-Chlorobutanone
- 1-Ethoxyethanol
Answer
11123.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.69)
Back
Check Point 23-2B
Give the IUPAC name for each of the following
compounds (c) (d)
(c) 2-Amino-3-hydroxypentanoic acid (d) 4-Hydroxy-
2-methylpentanamide
Answer
11223.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.69)
Let's Think 1
A student has given the wrong names for the
following organic compounds. Try to guess the
structural formulae and the correct names for
these compounds (a) 3-Hydroxy-3-ethylbutanoic
acid (b) 2-Chloro-3-cyano-1-methylpropane (c)
Propoxyethane
Answer
11323.2 Nomenclature of the Derivatives of
Hydrocarbons (SB p.69)
Back
11423.3 Nomenclature of the Derivatives of Aromatic
Hydrocarbons (SB p.72)
Example 23-3
Give the structural formula for each of the
following compounds (a) 1,4-Dichlorobenzene (b)
3-Nitrobenzoic acid
Answer
11523.3 Nomenclature of the Derivatives of Aromatic
Hydrocarbons (SB p.72)
Back
Example 23-3
Give the structural formula for each of the
following compounds (c) 4-Bromotoluene (d)
3,5-Dinitrophenol
Answer
11623.3 Nomenclature of the Derivatives of Aromatic
Hydrocarbons (SB p.72)
Check Point 23-3
Give the IUPAC name for each of the following
compounds (a)
(b)
Answer
(a) 2-Bromo-1,4-dichlorobenzene (b) 5-Bromo-2-chlo
robenzoic acid
11723.3 Nomenclature of the Derivatives of Aromatic
Hydrocarbons (SB p.72)
Back
Check Point 23-3
Give the IUPAC name for each of the following
compounds (c)
(d)
Answer
(c) 2,4-Difluorobenzenesulphonic
acid (d) 4-Hydroxybenzoic acid