Given the following structure: $\mathrm{CH}$₃-CH₂-CH=CH-CH₂-CH₂-CH₃, what is the correct IUPAC name for this molecule?

• A. $3$-hexene
• B. $3$-heptyne
• C. $3$-hexyne
• D. $3$-heptene

Answer: (D)

Verified step by step guidance

1. Identify the longest carbon chain that contains the double bond. Count the number of carbons in this chain to determine the root name (alkene with 7 carbons corresponds to 'heptene').
2. Number the carbon chain from the end nearest to the double bond to give the double bond the lowest possible number. This number indicates the position of the double bond.
3. Locate the double bond and assign its position number. In this molecule, the double bond is between carbons 3 and 4, so the position is 3.
4. Combine the position number with the root name and the suffix for the double bond. The suffix '-ene' indicates an alkene (double bond), so the name becomes '3-heptene'.
5. Verify that there are no other functional groups or substituents that would change the naming priority or add prefixes. Since none are present, '3-heptene' is the correct IUPAC name.