Which of these is the systematic name for the compound represented below? 2-ethylbutane 3-methylpentene 3-methyl-1-pentene 3-methyl-1-hexene 2-methylhexane
The Correct Answer and Explanation is:
Correct Answer: 3-methyl-1-hexene
Explanation:
To determine the correct systematic IUPAC name of a hydrocarbon compound, the structure must be analyzed based on the rules of organic nomenclature. The image referred to likely shows a hydrocarbon with a double bond and a substituted alkyl group, based on the options presented. The following steps guide the identification:
- Longest Carbon Chain Containing the Double Bond:
The priority is to find the longest continuous chain that includes the double bond. In this case, a six-carbon chain is present with the double bond starting at the first carbon, indicating the suffix “hexene”. - Numbering the Chain:
The chain must be numbered from the end nearest the double bond. This gives the double bond the lowest possible number. The double bond begins at carbon 1, so the base name becomes “1-hexene”. - Identifying Substituents:
A methyl group is attached to the third carbon of the main chain. This substituent is named “3-methyl”. - Combining the Components:
The compound name is formed by combining the position of the substituent, the name of the substituent, the position of the double bond, and the name of the main chain:
3-methyl-1-hexene. - Eliminating Incorrect Options:
- 2-ethylbutane: Lacks a double bond and contains only four carbons in the main chain.
- 3-methylpentene: Only five carbons; incorrect chain length.
- 3-methyl-1-pentene: Five-carbon chain; too short.
- 2-methylhexane: Saturated (no double bond).
The only option that accurately describes a six-carbon chain with a double bond starting at carbon 1 and a methyl group on carbon 3 is 3-methyl-1-hexene.
