Name the following alkenes:

SOLUTION:

a)
1. Main chain: 4 carbons with double bond (butene)
2. Numbering: lowest locant to the double bond.
3. Substituents: no
4. Name: But- 1 -ene b

)
1. Main chain: 5 carbons with double bond (pentene)
2. Numbering: lowest locator to the double bond.
3. Substituents: no
4. Name: Pent- 2 -ene


c)



1. Main chain:




4 carbons with two double bonds (butadiene)
2. Numbering: ends , we number so that the methyl takes the minor locator.
3. Substituents: methyl in position 2 .
4. Name: 2-Methylbuta- 1,3 - diene


d)
1. Main chain: 9 carbons with two double bonds (nonadiene ) 2.
Numbering: lowest locator to the double bonds ( 2,6 ).
3. Substituents: methyls in position 4,7 .
4. Name: 4,7 -Dimethylnona- 2,6 -diene {note}The longest chain is chosen as the main chain, which contains the greatest number of double bonds{/note}

e
)
1. Main chain: 6 carbons with two double bonds (hexadiene).
Note that it is not the longest. 2. Numbering: lowest locant to the double bonds ( 1,4 ).
3. Substituents: 2 -position ethyl and 5 .
4. Name: 2 -Ethyl- 5 -methylhexa- 1,4 -diene
f)
1. Main chain: 8 carbons with two double bonds (octadiene)
2. Numbering: lowest locant to the double bonds (
1,4 ) .
3. Substituents: methyls in position 7,7 .
4. Name: 7,7 -Dimethylocta- 1, 4-diene { note}The main chain is numbered so that the double bonds take the smallest locants{/note}