Question

To form alkane isonitrile, alkyl halide is reacted with:

• A. $KCN$
• B. $AgCN$
• C. $HCN$
• D. $N{H}_{4}CN$

Answer 1

The correct option is B $AgCN$

Among the given species, only in $AgCN$ there is a predominant covalent bond between $Ag-C$. Thus, C site is not available for nucleophilic attack. Hence, the lone pair of N attacks the alkyl halide, and isocyanide is formed as the major product.
$RX+AgCN\to RNC$