Question

The following IUPAC name is incorrect. Explain why it is incorrect and give the correct IUPAC name.

2-methyl-2-isopropylheptane

O The compound name is spelled incorrectly.
O The longest chain was not chosen.
O The compound has incorrectly labeled substituents.
O The compound name contains incorrectly alphabetized substituents.

Answer 1

The IUPAC names '2-ethylhexane' and '3-butyl-7-methyloctane' are incorrect due to the improper identification of the longest carbon chain. The correct longest chain should be identified as a heptane, with subsequent proper numbering and naming of substituents.

Step-by-step explanation:

The IUPAC name provided as 2-ethylhexane is incorrect because the longest chain contains seven carbon atoms, not six. The correct name for this molecule should reflect the longest chain as a heptane, leading to the proper identification of substituents.

For the compound 3-butyl-7-methyloctane, the naming is incorrect as well because the longest chain determination is flawed. Upon finding the correct longest chain and identifying the substituents and their positions, the correct name must ensure that substituents yield the lowest possible numbers when the chain is numbered. In this case, a molecule with a seven carbon chain is properly named as a heptane, with appropriate substituents. An example would be 3-ethyl-2,2-dimethylheptane, where the ethyl and methyl groups are correctly placed and named in the IUPAC nomenclature.