1,3-butadiene reacts with ethylene to form

Options

A. Benzene
B. Cyclohexane
C. Cyclohexene
D. 2, 3 dimethyl butane

Answer

To solve the problem of what product is formed when 1,3-butadiene reacts with ethylene, we can follow these steps:

### Step 1: Identify the Reactants
1,3-butadiene is an alkadiene with the formula C4H6, and ethylene (or ethene) is an alkene with the formula C2H4.

### Step 2: Write the Structural Formulas
- **1,3-butadiene**: The structure can be represented as:

CH2=CH-CH=CH2

- **Ethylene**: The structure is:

CH2=CH2

### Step 3: Determine the Reaction Conditions
The reaction typically requires heat, and in this case, it is mentioned that the reaction occurs at a temperature of 200 degrees Celsius.

### Step 4: Predict the Product
When 1,3-butadiene reacts with ethylene under heat, a Diels-Alder reaction can occur. This reaction involves the formation of a cyclohexene structure.

### Step 5: Write the Product Structure
The product formed from the reaction is cyclohexene, which can be represented as:

CH2-CH2
| |
CH2-CH
| |
CH2

### Step 6: Conclusion
The product formed when 1,3-butadiene reacts with ethylene is **cyclohexene**.

### Final Answer
The final answer is cyclohexene.

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