The IUPAC name of following compound is: $CH_3-C(=O)-CH_2-CH_2-CH_2-C(=O)-OH$

Question

Accepted Answer

The compound given is $CH_3-C(=O)-CH_2-CH_2-CH_2-C(=O)-OH$. To determine the IUPAC name, we need to identify the functional groups and the longest carbon chain, and then apply the IUPAC naming rules.

1. **Identification of Functional Groups:**
   - The compound contains a carboxylic acid group (-COOH) at one end and a ketone group (C=O) within the chain.

2. **Longest Carbon Chain:**
   - The longest continuous carbon chain in the compound has six carbon atoms. This makes the base name "hexanoic acid" because the carboxylic acid group takes priority in naming.

3. **Position of the Ketone Group:**
   - The ketone group is located on the second carbon when counting from the carboxylic acid end, which is the priority functional group. Therefore, the ketone is at position 5 when the carboxylic acid is at position 1.

4. **Correct IUPAC Name:**
   - The correct IUPAC name is "5-Oxohexanoic acid." The "5-oxo" indicates the position of the ketone group on the fifth carbon of the hexanoic acid chain.

**Explanation of Incorrect Options:**

1. **Option 1: 6-carboxy hexan-2-one**
   - This name incorrectly suggests that the carboxylic acid group is at position 6, which is not possible as it is at the end of the chain. Additionally, the ketone is not at position 2 when the carboxylic acid is the priority group.

3. **Option 3: Butyl methyl ketone**
   - This name suggests a ketone with a butyl group and a methyl group, which does not accurately describe the structure of the compound. It does not account for the carboxylic acid group.

4. **Option 4: 1,5-Diketohexanol**
   - This name suggests two ketone groups and an alcohol group, which is incorrect. The compound has one ketone group and one carboxylic acid group, not an alcohol group.

In conclusion, Option 2, "5-Oxohexanoic acid," is the correct IUPAC name for the given compound, as it accurately reflects the structure with a ketone group at the fifth position and a carboxylic acid group at the first position of the hexanoic acid chain.