Question

The IUPAC name of the compound $\mathrm{CH}{}_3\mathrm{CH}=\mathrm{CHC}\equiv \mathrm{CH}$ is

• A. Pent - 3 - en - 1 - yne
• B. Pent - 2 - en - 4 - yne
• C. Pent - 1 - en - 3 - ene
• D. Pent - 4 - en - 2 - ene

Answer 1

Answer: (A)

According to IUPAC nomenclature,
a. There are total 5 carbon atoms in the backbone chain. So the root word should be Pent.
b. Triple will be given more priority than the double bond. But in the name of the compound "ene" will be written before "yne" irrespective of the priority.
So the name of the compound is Pent-3-en-1-yne.