# Why do amides react differently with PCl5? [duplicate]

In a reaction involving $\ce{PCl5}$ and any reactant containing oxygen atom, it generally takes out the oxygen and put chlorine their due to formation of strong bond between phosphorus and oxygen.

But, in case of amides like $\ce{RCONH2}$, when they react with $\ce{PCl5}$, a cyanide is formed. Why?