Question

The correct IUPAC name of the compound

is:

• A. 4-ethyl-1-fluoro-2-nitrobenzene
• B. 4-ethyl-1-fluoro-6-nitrobenzene
• C. 3-ethyl-6-fluoro-1-nitrobenzene
• D. 1-ethyl-4-fluoro-3-nitrobenzene

Answer 1

The Correct Option is A

To name this compound according to IUPAC rules:

1. Identify the parent chain: The parent chain is the benzene ring.
2. Number the substituents: The substituents are ethyl, fluoro, and nitro. Numbering should be done to give the lowest possible numbers to the substituents. Since the nitro group has the highest priority alphabetically, we try to give it the lowest number. We can number it as 1, but then ethyl and fluoro would be 4 and 5 respectively. If we start numbering with fluoro as 1, then the nitro group becomes 2 and the ethyl group becomes 4, resulting in lower overall numbers (1, 2, 4 is better than 1, 4, 5).
3. Arrange the substituents alphabetically: The substituents are ethyl, fluoro, and nitro.
4. Combine the substituents and parent chain: The IUPAC name is 4-ethyl-1-fluoro-2-nitrobenzene.