Question

$RCl$ is treated with $Li$ in ether solution to form $RLi.RLi$ reacts with water to form is octane. $RCl$ also reacts with $Na$ to form $2,7$-dimethyl-octane. What is the structure of $RCl$ ?

• A. Octyl-chloride
• B. 2-chloro-2-methyl-butane
• C. Dimethyl-chloro-octane
• D. Isopentyl-chloride

Answer 1

Answer: (D)

$RCl$ reacts with $Na$ to give $2,7$-dimethyl octane (by Wurtz reaction).
$R-Cl+2Na+ClR\to R-R+2NaCl$
Hence,
Here,
$RLi$ reacts with water to form isopentane.

Therefore, $RCl$ is