1. SIDE-GROUP ISOMERS

2. SIDE-GROUP ISOMERS Isomers
- Isomers are chemicals which have the same chemical formula, but different arrangement of atoms.
- Nomenclature should help differentiate one isomer from another.

3. SIDE-GROUP ISOMERS Propyl isomers: n-propyl group isopropyl group CH3
CH3-CH2-CH2-CH2-CH-CH2-CH2-CH2-CH2-CH3
CH3-CH-CH3 l
CH3-CH2-CH2-CH2-CH-CH2-CH2-CH2-CH2-CH3

4. SIDE-GROUP ISOMERS
Propyl isomers:
n-propyl group
isopropyl group

5. SIDE-GROUP ISOMERS Butyl isomers: n-butyl group sec-butyl group
isobutyl group tert-butyl group
(t-butyl)
CH3 l
CH2
CH3-CH-CH2-CH3 l
CH3-CH2-CH2-CH2-CH-CH2-CH2-CH2-CH3
CH3-CH2-CH2-CH2-CH-CH2-CH2-CH2-CH3
CH3-CH-CH3 l
CH2
CH3 l
CH3-C-CH3
CH3-CH2-CH2-CH2-CH-CH2-CH2-CH2-CH3
CH3-CH2-CH2-CH2-CH-CH2-CH2-CH2-CH3

6. SIDE-GROUP ISOMERS Butyl isomers: n-butyl group sec-butyl group
isobutyl group tert-butyl group
(t-butyl)

7. SIDE-GROUP ISOMERS Terms: Iso – “equal”/”middle” Sec – “secondary”
Tert – “tertiary”
CH3-CH2-CH2-CH2-CH-CH2-CH2-CH2-CH3
CH3-CH-CH3 l
CH2
(unlike prefixes like “di” and “tri”, the “i” in iso affects the alphabetical order)
CH3-CH2-CH2-CH2-CH-CH2-CH2-CH2-CH3
CH3-CH-CH2-CH3 l
2 carbons adjacent to the carbon that is attached to the main chain
CH3-CH2-CH2-CH2-CH-CH2-CH2-CH2-CH3
CH3 l
CH3-C-CH3
3 carbons adjacent to the carbon that is attached to the main chain

8. SIDE-GROUP ISOMERS IUPAC naming system: Name the following molecules
5-tert-butylnonane
4-isopropylhept-1-ene

9. AROMATIC HYDROCARBONS

10. AROMATIC HYDROCARBONS
Aromatic hydrocarbons contain a benzene ring, C6H6, as a base
Most of these compounds are volatile (easily vaporized) and are associated with a distinct aroma (good or bad)

11. AROMATIC HYDROCARBONS
IUPAC naming system:
With side-chains, aromatic naming follows similar rules as for C-chains.
methylbenzene
chlorobenzene
ethylbenzene

12. AROMATIC HYDROCARBONS
IUPAC naming system:
When benzene is considered to be a side group, it is called a phenyl group
3-phenylheptane

13. AROMATIC HYDROCARBONS
IUPAC naming system:
When only two groups are present on benzene, the following prefixes are used:
ortho
meta
para
o-dimethylbenzene
m-dimethylbenzene
p-dimethylbenzene
1,2-dimethylbenzene
1,3-dimethylbenzene
1,4-dimethylbenzene

14. AROMATIC HYDROCARBONS
Solve these Rebus puzzles: