Which of the follolwing compounds undergoes easy decarboxylation on heating ?

Options

A.
B.
C.
D.

Answer

To determine which of the given compounds undergoes easy decarboxylation upon heating, we need to analyze the structures of the compounds provided. Decarboxylation is the process of removing a carboxyl group (-COOH) from a molecule, releasing carbon dioxide (CO2) in the process. This reaction is particularly favorable in beta-keto acids due to their stable enol forms.

### Step-by-Step Solution:

1. **Identify the Compounds**:
We need to look at the structures of the compounds provided in the question. Let's assume we have four compounds labeled A, B, C, and D.

2. **Check for Beta-Keto Acids**:
Beta-keto acids are known to undergo decarboxylation easily. A beta-keto acid has the structure R-CO-COOH, where the carboxylic acid group is adjacent to a ketone group.

3. **Analyze Compound A**:
- Compound A has a phenyl group attached to a carbon that is also bonded to a carbonyl (C=O) and a carboxylic acid (-COOH).
- This structure indicates that it is a beta-keto acid. Therefore, it can undergo decarboxylation upon heating.

4. **Analyze Compound B**:
- Compound B is a cyclic structure with a double bond and a carboxylic acid group.
- If this compound also has a ketone group adjacent to the carboxylic acid, it is also a beta-keto acid and will undergo decarboxylation.

5. **Analyze Compound C**:
- Compound C has a trifluoromethyl group (CF3) attached to a carbon that is also bonded to a carbonyl and a carboxylic acid.
- The CF3 group is a strong electron-withdrawing group, which decreases the electron density on the adjacent carbon. This makes the decarboxylation less favorable, and thus this compound will not undergo decarboxylation easily.

6. **Analyze Compound D**:
- Compound D has a hydroxyl group (-OH) and a carboxylic acid group.
- Since there is no adjacent ketone group, this compound does not fit the criteria for easy decarboxylation.

7. **Conclusion**:
- From the analysis, Compounds A and B are beta-keto acids and can undergo decarboxylation upon heating.
- Compounds C and D do not undergo decarboxylation easily due to the presence of the CF3 group and the lack of a ketone group, respectively.

### Final Answer:
The compounds that undergo easy decarboxylation upon heating are **Compound A and Compound B**.