2-Brumo butane when treated with Na in the presence of dry ether gives

Options

A. 3,4-dimethyl hexane
B. 3,3-dimethyl hexane
C. hexane
D. none

Answer

To solve the question regarding the reaction of 2-Bromobutane with sodium in the presence of dry ether, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Reactants**:
- The reactant is 2-Bromobutane, which has the structure:
\[ CH_3-CHBr-CH_2-CH_3 \]
- It contains four carbon atoms and a bromine atom attached to the second carbon.

2. **Understand the Reaction Conditions**:
- The reaction involves sodium metal (Na) and dry ether. This setup indicates that we are likely dealing with a Wurtz reaction.

3. **Wurtz Reaction Mechanism**:
- In a Wurtz reaction, two alkyl halides react with sodium to form a higher alkane.
- The general reaction can be represented as:
\[ 2 R-X + 2 Na \rightarrow R-R + 2 NaX \]
- Here, \( R \) represents the alkyl group and \( X \) is the halogen (in this case, bromine).

4. **Set Up the Reaction**:
- For 2-Bromobutane, we will use two equivalents:
\[ 2 \, CH_3-CHBr-CH_2-CH_3 + 2 \, Na \rightarrow \text{Higher Alkane} + 2 \, NaBr \]

5. **Determine the Product**:
- When the two 2-Bromobutane molecules react, the bromine atoms will be replaced by a bond between the two butyl groups.
- The resulting product will be:
\[ CH_3-CH(CH_3)-CH_2-CH_3 \]
- This compound has a total of 6 carbon atoms, which can be named as 3,4-dimethylhexane.

6. **Final Product and By-products**:
- The final product is 3,4-dimethylhexane.
- The by-products of the reaction are two molecules of sodium bromide (NaBr).

### Conclusion:
The reaction of 2-Bromobutane with sodium in the presence of dry ether produces 3,4-dimethylhexane and sodium bromide.