Question

The IUPAC name of the compound CH₃---CH₂--CH=CH₂ is

• A. But-3-ene
• B. But-1-ene
• C. But-3-yne
• D. But - 1 -yne

Answer 1

The Correct Option is B

The given compound contains two double bonds (\( \text{C}=\text{C} \)) and five carbon atoms in the longest chain. The numbering starts from the end closest to the first double bond to give the lowest possible numbers to the double bonds. The double bonds are located at positions 1 and 3:

\[ \text{IUPAC name: Buta-1,3-diene}. \]

However, since the options provided do not include "Buta-1,3-diene," we focus on the position of the first double bond (position 1). The compound is named as \( \text{But-1-ene} \).

Final Answer: The IUPAC name of the compound is \( \mathbf{\text{But-1-ene}} \), which corresponds to option \( \mathbf{(2)} \).