Question

What is IUPAC name of the following compounds?

Answer 1

3-hydroxy-4-methylbenzoic acid

Answer 2

1. The highest priority group is the carboxylic acid (–COOH), so the benzene ring is treated as a benzoic acid derivative.

2. Number the ring so that the –COOH group is at position 1.

3. With –COOH at C1, the substituents fall at:

   • C3: –OH group

   • C4: –CH₃ group

4. Hence, by IUPAC rules, the name is:

   $$\textbf{3-hydroxy-4-methylbenzoic acid}$$

Core Explanation:

• Carboxylic acid group has highest priority → assign position 1.
• Number ring so that –OH is at C3 and –CH₃ at C4.
• Therefore, name becomes 3-hydroxy-4-methylbenzoic acid.