Question

Common name of Benzene-1, 2-diol is

• A. quinol
• B. resorcinol
• C. catechol
• D. o-cresol

Answer 1

The Correct Option is C

The structure of Benzene-1,2-diol is:

The IUPAC name is Benzene-1,2-diol, and its common name is catechol.

Answer 2

Step 1: Identify the given compound
The compound is Benzene-1,2-diol. The name indicates a benzene ring with two hydroxyl (–OH) groups attached to adjacent carbon atoms (positions 1 and 2).

Step 2: Recognize its structural feature
Since both hydroxyl groups are on adjacent carbons of the aromatic ring, the compound is an ortho-dihydroxybenzene. The general structure can be written as:
\[ \text{C}_6\text{H}_4(\text{OH})_2 \] with hydroxyl groups at positions 1 and 2.

Step 3: Recall common (trivial) names of dihydroxybenzenes
There are three isomers of dihydroxybenzene depending on the relative positions of the –OH groups:
1. Benzene-1,2-diol → ortho-dihydroxybenzene → catechol
2. Benzene-1,3-diol → meta-dihydroxybenzene → resorcinol
3. Benzene-1,4-diol → para-dihydroxybenzene → hydroquinone

Step 4: Conclude the common name
Therefore, the compound Benzene-1,2-diol is commonly known as catechol.

Final answer

catechol