What is the correct IUPAC name of [figure] ?
- 3-Bromo-2-hydroxy-5-nitrobenzoic acid
- 2-Hydroxy-3-bromo-5-nitrobenzoic acid
- 3-Bromo-4-hydroxy-1-nitrobenzoic acid
- 5-Nitro-3-bromo-2-hydroxybenzoic acid
Answer
(1) 3-Bromo-2-hydroxy-5-nitrobenzoic acid
Solution
Principal functional group: –COOH parent name benzoic acid, and the ring carbon carrying –COOH is C-1.
Numbering towards –OH: OH at 2, Br at 3, NO2 at 5 locant set 2, 3, 5
Numbering the other way: NO2 at 3, Br at 5, OH at 6 locant set 3, 5, 6
The lowest locant set is 2, 3, 5.
Prefixes in alphabetical order: bromo, hydroxy, nitro.
IUPAC name: 3-Bromo-2-hydroxy-5-nitrobenzoic acid
Answer: (1)