The IUPAC name of the following compound is

The correct answer is Option (1) → 4-Chloro-2,3-dimethylpentan-1-ol

To name an alcohol by the IUPAC system:

• choose the longest carbon chain that contains the carbon carrying the –OH group, and name it with the suffix -ol in place of the final -e of the alkane;

• number the chain from the end nearer to the –OH group;

• name the other groups as prefixes with their locants, in alphabetical order (chloro before methyl; the “di” of dimethyl is ignored).

The compound is \( \ce{CH3-CH(Cl)-CH(CH3)-CH(CH3)-CH2OH} \). The longest chain through the \( \ce{CH2OH} \) carbon has five carbon atoms (pentan-), and numbering starts at the \( \ce{CH2OH} \) carbon:

    \( \displaystyle \text{C-5: }\ce{CH3} \quad \text{C-4: }\ce{CH(Cl)} \quad \text{C-3: }\ce{CH(CH3)} \quad \text{C-2: }\ce{CH(CH3)} \quad \text{C-1: }\ce{CH2OH} \)

This puts the –OH group at C-1, methyl groups at C-2 and C-3, and the chlorine at C-4. So the name is 4-Chloro-2,3-dimethylpentan-1-ol.

NCERT (2026-27 edition):
Nomenclature – …