Functional Groups - Alkenes and Alkynes

Alkenes and Alkynes



Name Functional Group
Structure
Example Compound Official Name of Example
(Common Name)
Formal Name Ending
alkene ethene
(ethylene)
-ene endings
alkyne ethyne
(acetylene)
-yne endings


Alkenes

Hydrocarbons that contain one or more carbon-carbon double bonds are called alkenes. They are named the same way as alkanes except that an -ene ending is used and the location of the double bond is identified. To locate the double bond, the longest carbon chain is numbered such that the double bond has the lowest number possible. In cyclic structures the double bond is always assumed to be on the first carbon.

is 2-pentene (not 3-pentene)

is cyclohexene


Alkynes

Hydrocarbons that contain one or more carbon-carbon triple bonds are called alkynes. They are named exactly the same way as alkenes except that the ending is -yne.

is 2-pentyne (not 3-pentene)


Continue reading about aromatics.


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