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Is there a way for the 4-methylcyclohexyl cation (4-methylcyclohex-1-ylium) to undergo some rearrangement and become tertiary carbocation via 1-3 or 1-4 shift?

4-methylcyclohex-1-ylium

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    $\begingroup$ Ring contraction... $\endgroup$ – Mithoron Dec 16 '16 at 19:20
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1,3- and 1,4- shifts don't really happen. It's just too far away. If you have a double bond at 4 or 5 carbons away, maybe you can do a ring closure or form a non-classical carbocation. The cation you've drawn could however undergo a sequence hydride shifts. Each hydride shift would move the cation closer to the methyl group, until the 3rd shift places the cation on the tertiary carbon. You'd need to out-compete any kind of elimination or cation reaction with a nucleophile...

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  • $\begingroup$ Ok so though not impossible , but 1-3 or 1-4 would rarely happen right? $\endgroup$ – Abhilasha Dec 16 '16 at 16:52
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    $\begingroup$ 1,3- and 1,4- are really weird. I doubt you'll ever get the stereoelectronics to line up for this. I've never seen an example (which, of course, doesn't mean it's impossible). $\endgroup$ – Zhe Dec 16 '16 at 19:37

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