Stability of the derivatives of cyclopropyl methyl carbocation

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Homework Statement
Is cyclopropyl cyclopentane carbocation also exceptionally stable or not?Give reason for you answer.
Relevant Equations
N/A
Here is an image of the structure
1587701886062-1365919611.jpg


I know that cyclopropyl methyl carbocation is exceptionally stable due to an effect so called dancing resonance which takes place because of lot of strain in cyclopropyl ring and vacant p orbital of Carbon attached with the ring.
So I think this is a similar situation as vacant p orbital of carbon which has positive charge attached with cyclopropyl ring has its vacant p orbital perpendicular to bonding orbital.So dancing resonance can take place here.So it should also be exceptionally stable.I don't know the answer.Am I correct?
 
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Physics lover said:
Homework Statement:: Is cyclopropyl cyclopentane carbocation also exceptionally stable or not?Give reason for you answer.
Relevant Equations:: N/A

Here is an image of the structure
View attachment 261298

I know that cyclopropyl methyl carbocation is exceptionally stable due to an effect so called dancing resonance which takes place because of lot of strain in cyclopropyl ring and vacant p orbital of Carbon attached with the ring.
So I think this is a similar situation as vacant p orbital of carbon which has positive charge attached with cyclopropyl ring has its vacant p orbital perpendicular to bonding orbital.So dancing resonance can take place here.So it should also be exceptionally stable.I don't know the answer.Am I correct?
Did anyone else tried it?
 
I think you’re probably right. I haven’t looked at the cyclopropyl cyclopentane cation specifically (i.e., there may be a weird rearrangement that I’m missing), but most substituted methylcyclopropyl cations are anomalously stable because of sigma resonance (cyclopropane C-C bonds donating into the empty p-orbital on the methyl cation). I don’t immediately see why this particular one would be different.
 
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TeethWhitener said:
Poked around a little more and found a few references to that molecule specifically:
Review article by Olah, et al.
Original article cited by above
It behaves as expected (enhanced stability, bisected geometry, etc).

Edit: the cyclobutyl/cyclopropyl cation, on the other hand, is apparently a big mess.
Thanks for that article.But I didn't understood why cyclobutyl/cyclopropyl cation is a mess.