Name the compound HO-CH2-C≡C-CH2-C≡CH according to IUPAC nomenclature rules.

The compound is $\text{HO}-\text{CH}_{2}-\text{C}\equiv\text{C}-\text{CH}_{2}-\text{C}\equiv\text{CH}$.
The longest carbon chain containing the alcohol ($\text{OH}$) group and the two alkyne ($\text{C}\equiv\text{C}$) groups has 6 carbons.
This makes the parent chain hex.

If we number from left to right (starting from the carbon attached to $\text{OH}$):

• The alcohol ($\text{OH}$) group is at carbon 1.
• The first alkyne bond starts at carbon 2.
• The second alkyne bond starts at carbon 5. The locants are 1 (for -ol), 2, 5 (for -diyne).

If we number from right to left:

• The alcohol ($\text{OH}$) group is at carbon 6.
• The first alkyne bond starts at carbon 1.
• The second alkyne bond starts at carbon 4. The locants are 6 (for -ol), 1, 4 (for -diyne).

According to IUPAC rules, the principal functional group (alcohol) takes precedence in numbering. Therefore, numbering from left to right is correct, as it assigns the lowest possible number (1) to the carbon bearing the $\text{OH}$ group.

• Parent chain: hex- (for 6 carbons)
• Two alkyne groups at positions 2 and 5: -2,5-diyne
• Alcohol group at position 1: -1-ol

Combine these parts. The "e" from "diyne" is dropped before the "ol" suffix.
The name of the compound is: