8. 3 Nomenclature of alkynes 8.3A IUPAC Nomenclature Unbranched alkynes, for example, are named by replacing the -ane of the name of the corresponding alkane with the ending -yne. The chain is numbered in order to give the carbon atoms of the triple bond the lower possible numbers8.3 Nomenclature of alkynes 8.3A IUPAC Nomenclature Unbranched alkynes, for example, are named by replacing the –ane of the name of the corresponding alkane with the ending –yne. The chain is numbered in order to give the carbon atoms of the triple bond the lower possible numbers