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Simun Mishra posted an Question

May 13, 2020 • 16:00 pm

30 points

IIT JAM
Chemistry (CY)

Why in resonance structure (i) is greater then ( ii) ..?

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Simun mishra

only explain why in this pic i> ii when both the resonating structure have same conjugation .....? except hyperconjugation
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yeah we always prefer resonance over hyperconjugation over inductive effect.. here resonance is same, so we will move on hyperconjugation so according to hyperconjugation str I > II.and according to you if we ignore the hyperconjugation the we will apply inductive effect.. in str. I and II free radical resonate over 3 carbon atoms so str I is stabilized by +I effect of the four CH3 groups is greater than II where free radical is stabilized by two CH3 groups
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hope now your have cleared everything
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yes ...tqqq
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🙏🙏
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Suresh khokhar

in general terms we wrote down hyperconjugation is resonance but technically both aredifferent scenario so please once you read about hyperconjugation I send you a link those give you concept about hyperconjugation.
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Dinesh khalmaniya 1

check it to clear resonance and hyperconjugation
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Suresh khokhar

read about hyperconjugation
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Suresh khokhar

it's not a resonance it hyperconjugation .i send i link u clear your concept https://youtu.be/FB4H7l7RSYM
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yes suresh sir, but you know hyperconjugation is a type of resonance so sometimes we can use resonance. but technically it's wrong.😊
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but in the structure both hyperconjugation and resonance is given then we use separate term to check stability ordee
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yas dinesh sir . your are absolutely correct. first we follow resonance and than hyperconjugation . bcz resonance effect is higher than hyperconjugation.
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🙂
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yes😊
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Simun mishra

this
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Don't be confused we can use hyperconjugation rather than resonance.
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Dinesh khalmaniya 1

both have same allylic free radical but str 1 has more hyperconjugating str than II. so I is more stable than II.
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no I m asking only about resonance according to here given
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resonance ...i> ii ...so ...
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no, both have same resonance as both have allyllic free radical
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so why ..here written ..resonance = i> ii
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actually hyperconjugation is the type of resonance so sometimes we can write it resonance but when resonance and hyperconjugation both present so we can write both hyperconjugation and resonance to separate the factors. so don't be confused
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here .both the structure have pi sigma lonepair conjugation ....show why the resonance is i> ii
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