# Which will be more stable carbocation upon heterolysis of "C"-"Cl" bond?

Mar 23, 2018

Consider the consequence of the heterolysis you describe for each, in turn,

$\left(1\right)$

This would be stabilized by resonance,

$\left(2\right)$

The cyclic ether would be acting as an electron donating group, stabilizing the positive charge.

$\left(3\right)$

This is stabilized by hyperconjugation to the highest degree (3°).

$\left(4\right)$

This is a primary carbocation: a very unstable molecule.

As a result of this qualitative analysis, $\left(1\right)$ and $\left(3\right)$ are very close in stability, but I would wager $\left(1\right)$ is slightly more stable. Resonance is a very powerful effect.