1. 1.12 CYCLIC ALKANES cyclopropane cyclopentane cyclobutane
Chp 1.12 cyclic alkanes
1.12 CYCLIC ALKANES
cyclopropane
cyclopentane
cyclobutane

2. MORE CYCLOALKANES ( cyclo = ring ) cyclopentane cyclohexane
Chp 1.12 cyclic alkanes
MORE CYCLOALKANES
( cyclo = ring )
cyclopentane
MOST STABLE
cyclohexane

3. COMMON ORGANICS THAT CONTAIN RINGS
nicotine
cholesterol
mescaline
caffeine

4. 1.13 Naming cyclic alkanes

5. RINGS WITH ONE SUBSTITUENT
Chp 1.12 cyclic alkanes
RINGS WITH ONE SUBSTITUENT
sec-butylcyclohexane
No locant is needed.
With one substituent on a ring , it is automatically on carbon 1.

6. = SOME CYCLOALKANES C H C H C H C H 1,3-dimethylcyclopentane
Chp 1.12 cyclic alkanes
SOME CYCLOALKANES C H 3
1,3-dimethylcyclopentane
Drawn
differently
but same
name. C H 3 2 1 = 3 C H 3 2
Begin numbering the ring at one of the attached groups,
so that the attached groups have the lowest numbers. C H 3 2 4 3 1 2 2 1 3
3-ethyl-1,1-dimethylcyclobutane
1-ethyl-4-methylcyclohexane
The more substituted carbon
takes precedence even
though E comes before M.
E before M

7. C H C H C H C H C C H C H NAMES OF THE COMMON ALKYL GROUPS ARE
Chp 1.12 cyclic alkanes
NAMES OF THE COMMON ALKYL GROUPS ARE
ALSO USEFUL WITH CYCLIC COMPOUNDS
isopropylcyclohexane C H C H 3 C H 3
2-cyclohexylpropane C H 3 C C H 3 C H 3
tert-butylcyclopentane
You can base the
name on either the
RING
or the
LONGEST CHAIN
2-cyclopentyl-2-methylpropane

8. Chp 1.12 cyclic alkanes
Name This
1-isopropyl-2-methylcyclohexane

9. 1.14 Isomerism in cyclic alkanes
Constitutional isomerism
Stereoisomerism

10. Constitutional Isomers of
Chp 1.12 cyclic alkanes
Constitutional Isomers of
C7H14 C H 3 C H 3 C H 3 C H 3
1,3-dimethylcyclopentane
1,1-dimethylcyclopentane C H 3 C H 3
1,2-dimethylcyclopentane

11. More constitutional isomers of
Chp 1.12 cyclic alkanes
More constitutional isomers of
C7H14
CAN YOU THINK OF ANY MORE?

12. Stereoismerism in cyclic alkanes
1. Occurs in cyclic alkanes with two or more groups attached to the ring.
2. Attached groups do not have to be the same.
3. Attached groups must be on different carbon atoms.
4. The stereoisomers are named “cis” and “trans”

13. Stereoismerism in cyclic alkanes (cont)
We will only consider the stereoisomerism in rings with two attached groups.
1. cis : the groups are on the same side of the ring (above or below)

14. Stereoismerism in cyclic alkanes (cont)
2. trans : the groups are on opposite sides of the ring (one group above and one group below)

15. Stereoisomers of 1,3–dimethylcyclopetane
Chp 1.12 cyclic alkanes
Stereoisomers of 1,3–dimethylcyclopetane C H 3
cis-1,3-dimethylcyclopentane C H 3
trans-1,3-dimethylcyclopentane C H 3
cis-1,3-dimethylcyclopentane C H 3
trans-1,3-dimethylcyclopentane

16. Stereoisomers of 1,2–dimethylcyclopentane
Chp 1.12 cyclic alkanes
Stereoisomers of 1,2–dimethylcyclopentane C H 3
cis-1,2-dimethylcyclopentane C H 3
trans-1,2-dimethylcyclopentane C H 3
cis-1,2-dimethylcyclopentane C H 3
trans-1,2-dimethylcyclopentane

17. 1,1-dimethylcyclopentane
Chp 1.12 cyclic alkanes
1,1-dimethylcyclopentane C H 3
Neither cis nor trans
Attached groups must be on different carbon atoms

18. 1.15 Sources of alkanes

19. 1.16 Physical properties of alkanes
Water solubility
B.P. and M.P
Branched
Linear
Cyclo
Increasing M.W.

20. 1.17 Chemical Properties Combustion…… Write balanced equations
Energy source
CO2 and H2O are products
Write balanced equations

21. THE END