Question

Write IUPAC name of the following compound

• A. $3-\mathrm{Hydroxy}-2-\mathrm{methylpentanoic}\mathrm{acid}$
• B. $4-\mathrm{Methyl}-3-\mathrm{hydroxypentanoic}\mathrm{acid}$
• C. $3-\mathrm{Hydroxy}-4-\mathrm{methylpentanoic}\mathrm{acid}$
• D. $2-\mathrm{Methyl}-2-\mathrm{hydroxypentanoic}\mathrm{acid}$

Answer 1

The correct option is C

$3-\mathrm{Hydroxy}-4-\mathrm{methylpentanoic}\mathrm{acid}$

Determining the root word:

As there are five carbon atoms in the main chain, so the root word will be ‘pent’.

Determining the substituents:

There are two substituents in the 3^rd and 4^th position, “methyl" and ”hydroxy" respectively.

Determining the suffix,

As the functional group here is Carboxylic acid, so the suffix would be “oic acid”

The name for the compound would be $3-\mathrm{Hydroxy}-4-\mathrm{methylpentanoic}\mathrm{acid}$.