Which of the following products is formed when adipic acid is heated ?

Options

A.
B.
C.
D.

Answer

To determine the product formed when adipic acid is heated, we can follow these steps:

### Step 1: Identify the Structure of Adipic Acid
Adipic acid is a dicarboxylic acid with the chemical formula C6H10O4. Its structure can be represented as:

```
O
||
HOOC-CH2-CH2-CH2-COOH
```

### Step 2: Understand the Heating Process
When adipic acid is heated, it undergoes dehydration (removal of water) and decarboxylation (removal of carbon dioxide).

### Step 3: Dehydration Reaction
The first step involves the removal of water (H2O). This leads to the formation of an intermediate compound. The dehydration can be represented as follows:

```
O
||
C-CH2-CH2-CH2-C
```

### Step 4: Decarboxylation Reaction
Next, we consider the possibility of decarboxylation, which involves the loss of a CO2 molecule. The removal of CO2 from the intermediate compound leads to the formation of a cyclic compound.

### Step 5: Formation of Cyclopentanone
After the removal of CO2, we end up with a five-membered ring structure known as cyclopentanone. The structure can be represented as:

```
O
||
CH2-CH2
| |
CH2 CH2
```

### Conclusion
Thus, the product formed when adipic acid is heated is cyclopentanone, which has one less carbon atom than the original adipic acid.

### Final Answer
The correct product formed when adipic acid is heated is **cyclopentanone**.

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