Question

Identify the product obtained when 2- Chloro - 2 - methylbutane is reacted with sodium metal in presence of dry ether?

• A. \(2,2,3,3-\) tetramethyloctane
• B. \(3,3,4,4-\) tetramethyloctane
• C. \(2,2,3,3-\) tetramethylhexane
• D. \(3,3,4,4-\) tetramethylhexane

Hint:

Wurtz coupling joins two alkyl groups at the carbons that carried the halogen.

Answer 1

The Correct Option is D

Step 1: Understanding the Concept:
In the Wurtz reaction, two alkyl halide molecules react with sodium metal in dry ether to give an alkane with double the carbon skeleton: \(2\text{R-X} + 2\text{Na} \rightarrow \text{R-R} + 2\text{NaX}\).

Step 2: Structure of R:
2-Chloro-2-methylbutane is \((\text{CH}_3)_2\text{C(Cl)CH}_2\text{CH}_3\). The alkyl group R is \((\text{CH}_3)_2\text{C-CH}_2\text{CH}_3\) (tert-pentyl).

Step 3: Coupling:
\[ \text{CH}_3\text{CH}_2\text{C(CH}_3)_2-\text{C(CH}_3)_2\text{CH}_2\text{CH}_3 \]
The longest chain has 6 carbons: \(\text{C}_1\text{H}_3\)-\(\text{C}_2\text{H}_2\)-\(\text{C}_3\)(CH\(_3\))\(_2\)-\(\text{C}_4\)(CH\(_3\))\(_2\)-\(\text{C}_5\text{H}_2\)-\(\text{C}_6\text{H}_3\). Methyl groups sit on C-3 (two) and C-4 (two), so the name is 3,3,4,4-tetramethylhexane. Octane-based names have an 8 carbon chain and do not fit, because the product has only 10 carbons in total, 6 in the chain plus 4 methyls.

Final Answer:
The product is 3,3,4,4-tetramethylhexane, option (D). \[ \boxed{3,3,4,4\text{-tetramethylhexane}} \]