IUPAC Naming of Glycerol

Glycerol is a simple organic molecule with the chemical formula C₃H₈O₃. Its structure is CH₂(OH)CH(OH)CH₂(OH).

To determine the IUPAC name, we follow standard nomenclature rules:

• Identify the Parent Chain: The longest continuous carbon chain contains 3 carbons. The parent alkane name is propane.
• Identify Functional Groups: There are three hydroxyl (-OH) groups attached to the carbon chain. These indicate the molecule is an alcohol. The suffix for three alcohol groups is '-triol'.
• Number the Chain: Number the carbon chain from either end to give the hydroxyl groups the lowest possible locant numbers. In this case, the positions are 1, 2, and 3 regardless of the direction.
• Combine Name and Locants: Combine the parent name (propane), the locants (1,2,3), and the suffix (-triol).

Therefore, the IUPAC name is Propane-1,2,3-triol.

Comparing with Options

• Ethane-1,2-diol has 2 carbons and 2 -OH groups.
• Propan-1-ol has 3 carbons and 1 -OH group.
• 2-Methylpropan-1-ol has a branched 3-carbon chain with an -OH group.
• Propane-1,2,3-triol correctly identifies the 3-carbon chain and the three hydroxyl groups at positions 1, 2, and 3.

The correct IUPAC name for glycerol is Propane-1,2,3-triol.