Which of the following undergoes decarboxylation most readily on being heated ?

Options

A.
B.
C.
D.

Explanation

To determine which compound undergoes decarboxylation most readily upon heating, we need to identify the structure of the compounds provided in the options and see if they are beta-keto acids. Beta-keto acids are known to undergo decarboxylation easily due to their structural characteristics.

### Step-by-Step Solution:

1. **Understand Decarboxylation**:
- Decarboxylation is the process of removing a carboxyl group (-COOH) from a compound, resulting in the release of carbon dioxide (CO2).

2. **Identify Beta-Keto Acids**:
- Beta-keto acids have a carboxylic acid group (-COOH) at the alpha position and a ketone group (C=O) at the beta position. This structure allows for the formation of a six-membered transition state during decarboxylation, making the process more favorable.

3. **Analyze Given Options**:
- Look at each option and identify the position of the carboxylic acid and ketone groups:
- **Option A**: The ketone group is at the gamma position relative to the carboxylic acid. This is not a beta-keto acid.
- **Option B**: The carboxylic acid group is at the alpha position, and the ketone group is at the beta position. This is a beta-keto acid and can undergo decarboxylation readily.
- **Option C**: There are no ketone groups present. This cannot undergo decarboxylation.
- **Option D**: The ketone group is at the alpha position, which does not allow for easy decarboxylation.

4. **Conclusion**:
- Only **Option B** contains a beta-keto acid structure, which means it will undergo decarboxylation most readily upon heating.

### Final Answer:
- The compound that undergoes decarboxylation most readily on being heated is **Option B**.