How do you name alkynes?

1 Answer
Dec 30, 2016

Here are some of the rules for naming alkynes.


Alkynes are unsaturated hydrocarbons containing a triple bond, #"R-C≡C-R"#.

You name them the same way as you name alkanes, but you replace the ending -ane with -yne.

When there is more than one triple bond, you use the multiplying prefixes to
get -diyne, -triyne, etc.

Step 1. Find the longest continuous chain of carbons containing the triple bond.

For example, #"CH"_3"CH"_2"CH"_2"C≡CCH"_3# has six carbon atoms, so its base name is hexyne.

Step 2. Number the carbon atoms in the main chain from the end closer to the triple bond.


Insert the first number of the alkyne carbons as close as possible before the
ending -yne.

The name becomes hex-1-yne.

Step 3. If there are other substituents, list them alphabetically with their locating numbers.


For example, the compound above is 3-methylhexa-1,4-diyne.