Question

The IUPAC name of \( \text{CH}_3\text{CH}= \text{CH}_2\text{CHO} \) is

• A. 2-Hydroxybutanal
• B. 3-Hydroxybutanal
• C. 2-Hydroxypropanal
• D. None of these

Hint:

The IUPAC name for a compound is determined by identifying the longest chain containing the functional group and then numbering the chain to give the lowest possible numbers to the substituents.

Answer 1

The Correct Option is A

Step 1: Analyzing the structure of the compound.
The compound \( \text{CH}_3\text{CH}= \text{CH}_2\text{CHO} \) contains an aldehyde group (-CHO) attached to a carbon-carbon double bond, with a hydroxyl group (-OH) attached to the second carbon in the chain. Step 2: Determining the IUPAC name.
To name this compound according to IUPAC rules, we need to identify the longest chain containing the aldehyde group. The aldehyde is on the first carbon, and the hydroxy group is attached to the second carbon. Therefore, the name is 2-Hydroxybutanal. Step 3: Conclusion.
The correct answer is (A) because the IUPAC name is 2-Hydroxybutanal.