Question

The best method for preparation of ${Me}_{3}CCN$ is:

• A. to react ${Me}_{3}COH$ with $HCN$
• B. to react ${Me}_{3}CBr$ with $NaCN$
• C. to react ${Me}_{3}CMgBr$ with $ClCN$
• D. to react ${Me}_{3}CLi$ with ${NH}_{2}CN$

Answer 1

The correct option is C to react ${Me}_{3}CMgBr$ with $ClCN$

The reaction is a $S_{N}2$ reaction. Here, one bond is broken and another bond is formed synchronously.

$M{e}_{3}C-MgBr+Cl-CN\to M{e}_{3}C-CN+Mg\left(Cl\right)Br$

So, the correct option is $C$