Page 34 - Ranger SPM 2022 Chemistry

Chemistry SPM Chapter 2 Carbon Compound
5. Steps to identify and name isomers according to IUPAC nomenclature:
 Identify the longest continuous chain of carbon atoms.
 Carbon 1 from the longest straight chain of carbon atoms normally starts
from:
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(a) the carbon that is the nearest to the branched chain (alkyl group) for
alkane
(b) the carbon that is the nearest to the functional group for alkene, alkyne
and alcohol.
 Use prefixes such as di- (2), tri- (3), tetra- (4), or penta- (5) to indicate the
number of alkyl or functional group present in the compound. The numbers
indicating the alkyl or functional group must be separated by a comma (,).

–CH–CH 3 3 H H –C H–C H H HH H –C H–C H 7 7 H H HH H H
H
–C
–C
–CH
H

H H

H H
H
H
3
5 2
3
2
2
7 3
3
5 5

& & & && & & & && & &
&
&
& &
& &
Structural formula H!C!C! H!C!C!C! H!C!C!C!C!
C
C
C
H
H
C
H
C
C
C
H
H
H
C
C
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
& & & && & & & && & &

& &
&
& &
&
H

H H
H H H HH H H H HH H H
H

H H
Group Methyl Ethyl Propyl
 Complete the IUPAC nomenclature according to the format:
(Number of position of branch)-(name of branch)(name of parent chain)
Isomerism in Alkane Isomerism in Alkyne
Draw and name all the isomers from Draw and name all the isomers from
butane, C H . butyne, C H .
4 10 4 6
H H H H
H H
H C 1 C 2 C 3 C 4 H
H C 1 C 2 C 3 C 4 H
H H H H
H H
Form 5
Butane But-1-yne
H
Methyl H H
H C H
H H
H H C 1 C 2 C 3 C 4
H H
H C 1 C 2 C 3 H
But-2-yne
H H H
2-methylpropane
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02.5 RANGER SPM CHEMISTRY 2P.indd 163 29/03/2022 2:28 PM