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 \rightarrow R-R+2NaCl $
Hence,
Here,
$ RLi $ reacts with water to form isopentane.

Therefore, $RCl$ is