Question

Which statement is wrong about the hydrolysis of $R-\stackrel{\oplus }{N}\equiv \stackrel{\ominus }{C}$?

• A. Isocyanides are hydrolysed with aqueous dilute acids but not by alkali
• B. In the hydrolysis of $(R-\stackrel{\oplus }{N}\equiv \stackrel{\ominus }{C})$, first electrophile $\left(H^{\oplus }\right)$ adds on the C atom and then nucleophile $\left(\stackrel{\ominus }{OH}\right)$ adds to the same C atom
• C. On partial hydrolysis, $\left(RNC\right)$ gives N-substituted methanamide or formamide
• D. On complete hydrolysis $\left(RNC\right)$ gives $1^o$ amine and $RCOOH$.

Answer 1

The correct option is D On complete hydrolysis $\left(RNC\right)$ gives $1^o$ amine and $RCOOH$.

$RX$ in $\left(I\right)$ with $\stackrel{\ominus }{CN}$ gives $R-C\equiv N$, while $RX$ in $\left(II\right)$ with ${CN}^{\ominus }$ gives $R-\stackrel{\oplus }{N}\equiv \stackrel{\ominus }{C}$

Hydrolysis of RNC (Isocyanide) is shown in the above reaction from (G) to (J).
On partial hydrolysis, (RNC) gives N-substituted methanamide. The complete hydrolysis of Isocyanide gives Formic acid not RCOOH.

Hence, option D is the correct answer.