The compound that undergoes decarboxylation most readily under mild condition is

Options

A.
B.
C.
D.

Answer

To solve the question regarding which compound undergoes decarboxylation most readily under mild conditions, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Decarboxylation**:
- Decarboxylation is the process of removing a carboxyl group (-COOH) from a compound, releasing carbon dioxide (CO2). This reaction is common in carboxylic acids.

2. **Identifying Key Features**:
- Compounds that undergo decarboxylation readily often have specific structural features. Beta-keto acids (compounds with a keto group adjacent to the carboxylic acid) are known to undergo decarboxylation more easily than other types of carboxylic acids.

3. **Recognizing Beta-Keto Acids**:
- A beta-keto acid is characterized by having a keto group (C=O) on the beta carbon relative to the carboxylic acid group. This structure stabilizes the transition state during decarboxylation, making the reaction more favorable.

4. **Analyzing the Given Options**:
- Among the options provided, we need to identify which one is a beta-keto acid. The compound cyclohexanecarboxylic acid with a keto group at the 2-position is a beta-keto acid.

5. **Conclusion**:
- The compound that undergoes decarboxylation most readily under mild conditions is **2-oxo-cyclohexanecarboxylic acid** (option D). Upon decarboxylation, it produces cyclohexanone and carbon dioxide.

### Final Answer:
The compound that undergoes decarboxylation most readily under mild conditions is **2-oxo-cyclohexanecarboxylic acid** (option D).

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