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Answer given is a but how on earth is it possible because here one C Atom has 5 covalent bonds. Infact the aromatic character is decreased. I think c is correct because of resonance structure. But why the anser is a? Can anyone explain please?


For halogen is in meta position ? So -I effect of NO2 effecting?

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    $\begingroup$ The answer is (a), but the double bonds in it are drawn the wrong way (one carbon seems pentavalent, another trivalent). Mistakes happen. $\endgroup$ – Ivan Neretin Sep 29 '17 at 8:22
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    $\begingroup$ The main idea is that you don't want to end up with a (formal) positive charge next to a strongly electron-withdrawing group (EWG). No resonance structure of (a) (especially if it were drawn correctly) can have that, whereas in (b) that's already the case in the depicted structure (NO2 being the EWG), and in (c) you get that by shifting the two pi bonds in sequence. Not sure about (d); did they mean to put double bonds somewhere, or is it really this aliphatic cycle we're talking about? It's always sad to see such inaccurate and shabbily put together exam questions... how will students learn? $\endgroup$ – user6376297 Sep 29 '17 at 16:50
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Ok I got the idea. It's because of hyperconjugation (mainly) and then about like charges on resonating structures or normal structures will decrease the stability And so the order is

A>C>D>B Or A>D>C>B

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