IUPAC Nomenclature

IUPAC Nomenclature of alkynes is almost identical to that of alkenes, except instead of the root name of -ene used for alkenes, the root name of -yne is given.

2-hexyne

The above compound, for example, would be named 2-hexyne, the -yne ending indicating that it is an alkyne and the number telling the position of the triple bond. Alkynes are a lower-priority functional group than alkenes, so a compound that has both an alkene and an alkyne would have a root name of -ene.

Common Nomenclature

Alkynes are often named with a root name of acetylene, the simplest alkyne. Groups coming off the triple bond are named as substituents.

Acetylene	Methyl acetylene	Dimethyl Acetylene

PRACTICE PROBLEM

1. What is the IUPAC name of the following:

acetylene
di isopropyl acetylene
2,5-dimethyl-3-heptyne
2,5-dimethyl-3-hexyne

2. What is the common name of the following:

2,5-dimethyl-3-hexyne
2,5-dimethyl-3-heptyne
di isopropyl acetylene
di t-butyl acetylene

Score =
Correct answers: