1. Organic Chemistry C H H C C H C H H O C

2. Compare and contrast the structure of aromatic and aliphatic hydrocarbons.
Include: molecular models, structural formulas, common uses
Additional KEY Terms
resonance

4. Aliphatics - straight chains and cyclic-aliphatics.
Aromatics - benzene and its derivatives (variations)
- unsaturated
- named because of their smell/odour
All aromatic compounds contain a single modified benzene ring or groups of rings.

6. Benzene (C6H6):
simplest aromatic compound
a known carcinogen
colorless, highly flammable liquid
naturally occurring in crude oil
important industrial solvent and precursor in the
production of drugs, plastics, rubber, and dyes…

8. Almonds
Benzaldehyde
C7H6O
Citrus fruits
Limonene
C10H16

9. Optical Isomsers
Spearmint / Caraway
Carvone
C10H14O

10. Liquorice
Glycyrrhizin
C42H62O16

11. 6 electrons (one from each carbon) participate in double bonds.
These 6 e- are actually shared by all 6 carbons.
Two different correct structures for benzene - RESONANCE - to show the movement of the 6e-.

12. H C H H C C H C C H C H

13. H C H H C C H C C H C H

14. Molecules with double bond resonance are more stable than molecules of similar size.
Explains higher than expected melting point.

15. Naming compounds containing Benzene
1. Benzene is the parent chain when the ring is off
an end carbon of an alkane.
CH3
CH2 - CH2 - CH2 - CH3
butylbenzene
methylbenzene or "toluene"

16. Here the benzene ring is called a phenyl group
Benzene is a branch on ANY alkene / yne chain, OR when the benzene ring is in the middle of the alkane chain.
Here the benzene ring is called a phenyl group
CH3 - CH2 - CH - CH3
2-phenylbutane
CH2 - CH = CH2
3-phenylpropene

17. The Alkane exception to the Rule
If there are two branches on an alkane, the alkane is the parent chain and the benzene ring is named as a phenyl.
Even if the ring is on an end carbon
CH2 - CH2 - CH - CH3
CH3 -
3-methyl-1-phenylbutane

18. When benzene has 2 identical branches on the ring, the positions are given special names.
1,2 - ortho 1,3 – meta 1,4 - para. H
CH3
1,2-dimethylbenzene
o-dimethylbenzene
(o-xylene)

19. 1,3-dimethylbenzene
m-dimethylbenzene
(m-xylene)
1,4-dimethylbenzene
p-dimethylbenzene
(p-xylene)

20. 2-phenylbutane 3-phenylpropene methylbenzene butylbenzene
CH3 - CH2 - CH - CH3
2-phenylbutane
CH2 - CH = CH2
3-phenylpropene
CH3
CH2 - CH2 - CH2 - CH3
methylbenzene
butylbenzene

21. CAN YOU / HAVE YOU?
Compare and contrast the structure of aromatic and aliphatic hydrocarbons.
Include: molecular models, structural formulas, common uses
Additional KEY Terms
resonance