1. Chapter 10 Introduction to Organic Chemistry: Alkanes
10.3
Alkanes with Substituents

2. Isomers of Butane Isomers have the same molecular formula.
have different atom arrangements.
of butane (C4H10) are a straight chain and a branched chain.

3. Alkyl groups Alkyl groups are alkanes that are missing one H.
substituents attached to carbon chains.
named with a –yl ending. H
H C CH3 methyl
H H
H C C CH3 CH2 ethyl

4. Naming Substituents In the IUPAC system,
TABLE 10.6
In the IUPAC system,
a carbon branch is named as an alkyl group.
halogen atoms are named as halo.

5. Alkanes with Substituents
CH3
CH3 CH CH methylpropane
methyl groups
CH CH3
CH3 CH CH2 CH CH ,4-dimethylpentane

6. Naming Alkanes Give the name of CH3 CH3   CH3─CH─CH─CH3
 
CH3─CH─CH─CH3
STEP Name the longest continuous chain.
CH3 CH3
butane

7. Naming Alkanes Give the name of CH3 CH3   CH3─CH─CH─CH3
 
CH3─CH─CH─CH3
STEP Number chain. CH3 CH3
 
STEP 3 Locate substituents and name.
2,3-dimethylbutane

8. Learning Check
Write the name of
Cl CH3
 
CH3─CH2─CH─CH─CH3

9. Solution STEP 1 Longest chain is pentane.
STEP Number chain from end nearest substituent.
Cl CH3
 
CH3─CH2─CH─CH─CH3
STEP 3 Locate substituents and name alphabetically.
3-chloro-2-methylpentane

10. Learning Check Give the IUPAC name for each of the following:
A CH CH3
| |
CH3─CH─CH2 ─CH─CH3
B Cl CH3
CH3─CH2─CH─CH2─C─CH2─CH3 | Cl

11. Solution A. CH3 CH3 | | CH3─CH─CH2 ─CH─CH3 2,4-dimethylpentane
| |
CH3─CH─CH2 ─CH─CH ,4-dimethylpentane
B Cl CH more substituents = C3
CH3─CH2─CH─CH2─C─CH2─CH3 | Cl
3,5-dichloro-3-methylheptane

12. Learning Check Draw the condensed structural formula for
2-bromo-4-chlorobutane.

13. Solution 2-bromo-4-chlorobutane
STEP Longest chain has 4 carbon atoms.
C─C─C─C
STEP Number chain and add substituents. Br 
C ─ C ─ C ─ C ─ Cl
STEP 3 Add hydrogen to complete 4 bonds to each C.
CH3─CH─CH2─CH2─Cl

14. Naming Cycloalkanes with Substituents
The name of a substituent is placed in front of the
cycloalkane name.
methylcyclobutane CH3
chlorocyclopentane Cl

15. Learning Check
Name each of the following.
CH3
CH2─CH3 2.

16. Solution Name each of the following. 1. methylcyclopropane
2. ethylcyclohexane