Polyynes

Introductory IUPAC Organic Nomenclature

Polyynes

The term polyyne simply implies the presence of several alkynes. To be more specific, a diyne has two C≡C, a triyne has 3 C≡C etc.
Polyynes are named in a similar manner to alkynes themselves and to polyenes.

The root name is based on the longest chain containing both ends of all the alkyne units.
The chain is numbered so as to give the one of the alkyne units the lowest possible number (i.e. first point of difference).
The locant for the lowest numbered carbon of each alkyne is used in the name.
The appropriate multiplier (i.e. di- for two, tri for three) is inserted before the -yne suffix.
In order make the name pronounceable, -a- is inserted after the root.

Functional group is an alkyne, therefore suffix = -yne
There are two alkynes, so insert the multiplier di
The longest continuous chain is C6 therefore root plus "a" = hexa
The first point of difference requires that we number from the right as drawn
Locants for C≡C units are therefore 1- and 4-

1,4-hexadiyne

or
hexa-1,4-diyne

CH₃C≡CCH₂C≡CH