Give a systematic name for this molecule.

• A. 10-methyl-8-propyl-4-undecyne
• B. 10-methyl-8-propyl-4-undecane
• C. 8-sec-butyl-4-undecene
• D. 8-tert-butyl-4-undecene

Answer: (A)

Verified step by step guidance

1. Identify the longest carbon chain that contains the highest priority functional group. In this molecule, the highest priority group is the alkyne (triple bond), so find the longest chain that includes the triple bond. Count the carbons in this chain to determine the parent name (e.g., undecyne for 11 carbons with a triple bond).
2. Number the carbon chain starting from the end nearest the triple bond to give the alkyne the lowest possible number. This will determine the position of the triple bond (e.g., position 4 if the triple bond starts at carbon 4).
3. Identify and name all substituents (alkyl groups) attached to the main chain. Determine their positions by numbering the carbons in the main chain. For example, a methyl group at carbon 10 and a propyl group at carbon 8.
4. Combine the substituent names and their positions in alphabetical order, followed by the parent chain name with the position of the triple bond. Use hyphens to separate numbers and names, and commas to separate multiple numbers.
5. Write the full systematic name by putting it all together, such as '10-methyl-8-propyl-4-undecyne', ensuring correct use of prefixes, numbers, and the parent chain name indicating the triple bond.