Question

Catechol and m-cresol respectively are

• A. Benzene - 1, 4 - diol; 3 - Methoxy phenol
• B. Benzene - 1, 2 - diol; 3 - Methoxy phenol
• C. Benzene - 1, 3 - diol; 3 - Methyl phenol
• D. Benzene - 1, 2 - diol; 3 - Methyl phenol

Hint:

Remember the common names and corresponding IUPAC names for simple aromatic compounds with functional groups. Catechol is 1,2-dihydroxybenzene (ortho-diol), resorcinol is 1,3-dihydroxybenzene (meta-diol), and hydroquinone is 1,4-dihydroxybenzene (para-diol). Cresol refers to methylphenol, with ortho-, meta-, and para- isomers depending on the relative positions of the methyl and hydroxyl groups.

Answer 1

The Correct Option is D

Let's analyze the structures of catechol and m-cresol: **Catechol:** Catechol is also known as 1,2-dihydroxybenzene.
It consists of a benzene ring with two hydroxyl (\( -OH \)) groups attached to adjacent carbon atoms (positions 1 and 2).
Therefore, the IUPAC name for catechol is benzene-1,2-diol.
The structure of catechol is: **m-cresol:** Cresol is the common name for methylphenol.
The prefix "m-" (meta) indicates that the methyl (\( -CH_3 \)) group and the hydroxyl (\( -OH \)) group are attached to the benzene ring at positions 1 and 3 relative to each other.
If we consider the hydroxyl group to be at position 1 (as it gives the phenol base name), then the methyl group is at position 3.
Therefore, the IUPAC name for m-cresol is 3-methylphenol.
The structure of m-cresol is: Matching these IUPAC names with the options:
Option (A) Benzene - 1, 4 - diol; 3 - Methoxy phenol: Benzene-1,4-diol is hydroquinone, and 3-methoxy phenol is m-methoxyphenol (not m-cresol).

Option (B) Benzene - 1, 2 - diol; 3 - Methoxy phenol: Benzene-1,2-diol is catechol, but 3-methoxy phenol is not m-cresol.

Option (C) Benzene - 1, 3 - diol; 3 - Methyl phenol: Benzene-1,3-diol is resorcinol (not catechol), but 3-methyl phenol is m-cresol.

Option (D) Benzene - 1, 2 - diol; 3 - Methyl phenol: Benzene-1,2-diol is catechol, and 3-methyl phenol is m-cresol.
Thus, option (D) correctly identifies catechol as benzene-1,2-diol and m-cresol as 3-methyl phenol.