1,3-Dibromopropane reacts with metallic zinc to form

Options

A. propene
B. cycloprpopane
C. propane
D. hexane

Answer

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

### Step 1: Identify the Reactants
The reactant in this reaction is 1,3-Dibromopropane. Its structure can be represented as follows:
- It has bromine (Br) atoms attached to the first and third carbon atoms of a three-carbon (propane) chain.

### Step 2: Understand the Reaction Type
This reaction is a type of coupling reaction known as the Wurtz reaction, which involves the use of metallic zinc (Zn) to couple alkyl halides. In this case, we are dealing with a dibromopropane.

### Step 3: Mechanism of the Reaction
1. **Oxidation of Zinc**: The metallic zinc (Zn) gets oxidized to Zn²⁺, releasing two electrons (2e⁻).
2. **Formation of Carbanion**: The electrons from zinc will attack the carbon atoms bonded to the bromine atoms, leading to the homolytic cleavage of the C-Br bonds. This results in the formation of a carbanion intermediate.
3. **Cyclization**: The carbanion can then react with another carbon atom in the chain, leading to the formation of a cyclopropane structure. The bromine atom acts as a leaving group during this process.

### Step 4: Identify the Product
The final product of this reaction is cyclopropane, which is a three-membered carbon ring.

### Conclusion
Thus, when 1,3-Dibromopropane reacts with metallic zinc, the product formed is cyclopropane.

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