`OHC(CH_(2))_(3)COCH_(3)overset(OH^(-))underset(Delta)rarr`
The major product is ?

Options

A.
B.
C.
D.

Answer

To solve the problem, we need to analyze the reaction of the compound OHC(CH₂)₃COCH₃ in the presence of a base (OH⁻) and heat. This reaction involves aldehyde condensation, where we have both an aldehyde group (CHO) and a ketone group (COCH₃).

### Step-by-Step Solution:

1. **Identify Functional Groups**:
The compound has an aldehyde group (CHO) and a ketone group (COCH₃). The structure can be represented as:
\[ \text{CHO - CH}_2 - \text{CH}_2 - \text{CH}_2 - \text{CO - CH}_3 \]

2. **Recognize Reaction Type**:
The presence of a base (OH⁻) and heat indicates that we are dealing with an aldol condensation reaction. This reaction typically occurs between aldehydes or between an aldehyde and a ketone.

3. **Identify Alpha Hydrogens**:
Both the aldehyde and the ketone have alpha hydrogens. The aldehyde has three alpha hydrogens (from the CH₂ groups), and the ketone has one alpha hydrogen (from the CH₃ group).

4. **Deprotonation**:
The base (OH⁻) will deprotonate one of the alpha hydrogens to form an enolate ion. The enolate can form from either the aldehyde or the ketone.
- If the enolate forms from the aldehyde, it will be:
\[ \text{CH}_2 - \text{CH}_2 - \text{CH}_2 - \text{C}^- = \text{O} - \text{CH}_3 \]
- If it forms from the ketone, it will be:
\[ \text{C}^- - \text{O} - \text{CH}_3 \]

5. **Nucleophilic Attack**:
The enolate ion will then attack the carbonyl carbon of the other carbonyl compound present in the reaction.
- If the enolate was formed from the aldehyde, it will attack the ketone.
- If the enolate was formed from the ketone, it will attack the aldehyde.

6. **Formation of the β-Hydroxy Carbonyl Compound**:
After the nucleophilic attack, we will form a β-hydroxy carbonyl compound. This compound will have both the aldehyde and ketone functionalities.

7. **Dehydration**:
Upon heating, the β-hydroxy carbonyl compound will undergo dehydration (loss of water) to form an α,β-unsaturated carbonyl compound.

8. **Final Product**:
The final product will be a six-membered ring compound due to the formation of a stable cyclic structure during the reaction. The major product is an α,β-unsaturated carbonyl compound.

### Conclusion:
The major product of the reaction is an α,β-unsaturated carbonyl compound, which corresponds to the structure of a cyclohexene derivative.