Carbonyl compounds undergo nucleophilic addition because of :

Options

A. electronegativity difference of carbon and oxygen atoms
B. electromeric effect.
C. more stable anion with negative charge on oxygen and less stables carbocation
D. none of these

Explanation

To answer the question "Carbonyl compounds undergo nucleophilic addition because of:", we need to analyze the properties of carbonyl compounds and the nature of the nucleophilic addition reaction.

### Step-by-Step Solution:

1. **Understanding Carbonyl Compounds**:
- Carbonyl compounds contain a carbonyl group (C=O), which is a functional group consisting of a carbon atom double-bonded to an oxygen atom.

2. **Polarity of the Carbonyl Group**:
- The carbon-oxygen bond in carbonyl compounds is polar due to the difference in electronegativity between carbon and oxygen. Oxygen is more electronegative than carbon, which means it attracts the shared electrons more strongly.

3. **Partial Charges**:
- Because of this polarity, the carbon atom in the carbonyl group acquires a partial positive charge (δ+), while the oxygen atom acquires a partial negative charge (δ-). This creates a dipole moment in the molecule.

4. **Nucleophilic Attack**:
- Nucleophiles are species that have a negative charge or a lone pair of electrons and are attracted to positively charged or partially positively charged centers. In carbonyl compounds, the partially positive carbon atom acts as an electrophile, making it susceptible to attack by nucleophiles.

5. **Formation of Tetrahedral Intermediate**:
- When a nucleophile attacks the carbon atom of the carbonyl group, it forms a tetrahedral intermediate. This is a key step in the nucleophilic addition mechanism.

6. **Stability Considerations**:
- The reaction is favored because the resulting anion (after the nucleophile adds to the carbonyl carbon) is more stable than a carbocation that would form if the carbonyl compound were to undergo a different type of reaction. The negative charge is stabilized on the more electronegative oxygen atom.

7. **Conclusion**:
- Therefore, carbonyl compounds undergo nucleophilic addition due to the polar nature of the carbonyl group, which creates a favorable condition for nucleophilic attack, leading to the formation of a more stable anion.

### Final Answer:
Carbonyl compounds undergo nucleophilic addition because of the polar nature of the carbon-oxygen bond, which results in a partial positive charge on the carbon atom, making it susceptible to nucleophilic attack, and because the resulting anion is more stable than a carbocation.