Question

How many $\sigma$ and $\pi$ bonds will be in allyl isocyanide?

• A. $9\sigma$ and $3\pi$
• B. $9\sigma$ and $9\pi$
• C. $3\sigma$ and $4\pi$
• D. $5\sigma$ and $7\pi$

Answer 1

Answer: (A)

$9\sigma$ and $3\pi$

This is allyl isocyanide:

$CH2=CH-C{H}_2-N\equiv C$ with a formal negative charge (and unshared electron pair) on the need carbon and a formal positive charge on nitrogen.

The 9 sigma bonds come from the C-H bonds and one each from the $C-C$ bonds and the $C-N$ bond and 3 pi bonds. (2 bonds from $CN$ and one from $C{H}_2=C{H}^{-}$)