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I know that meta position shown no resonance effect and hyperconjugation effect . So According to the order given I guess Hyperconjugating effect is taken into account as -CH3 has no Resonance effects.

But are the hydrogen in methyl group alpha hydrogens ? As per I know that hyperconjugation is only shown if alpha hydrogen is present .

I am not getting the order . If only inductive effect was considered the order should have been 1>2>3 but its 1>3>2 please explain this order to me .

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First understand that resonance stabilized carbocation is much more stable than that of inductive stabilized one, so out of the three ones, one can conclude that I,III>II. Now the ambiguity arises in choosing between I and III, now we turn to inductive effect for help, and here in this case, is simple because in I the methyl group is closer to the cation than in III, so you can conclude I>III, based on the two conclusions, one can conclude the order.

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  • $\begingroup$ How can CH3 show resonance. Can you please elaborate $\endgroup$ – Harsh jain Oct 22 '18 at 15:57
  • $\begingroup$ The effect is called hyper conjugation, look it up on Google $\endgroup$ – Esha Manideep Oct 22 '18 at 17:08
  • $\begingroup$ Hyperconjugation is a different thing and its very less effective than resonance $\endgroup$ – Harsh jain Oct 23 '18 at 2:18

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