[g_orbital]

The following reaction exploits Lithium + ammonia in order to cleave the cyclopropyl ring. Usually, I'm used to see these reagents as "Birch condition" for reduction of aromatic compounds or alpha,beta-unsaturated ketone. But here, I fail to understand the mechanism of the reaction (It seems radical, however).

I'll appreciate your assistance.
Thank you

[miraculix]

Hello,

I would suppose you're generating a Ketyl-radical under these reaction conditions.
Therefore, you will have a cyclopropyl-ketylradical.
These radical are known to undergo a very fast (one of the fastest) ring opening reactions.
The same would probably happen with SmI₂.

cheers
miraculix