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Why is resonance possible in phenoxide anion as when the electron pair of oxygen is involved in conjugation we have 4 pairs of electrons in resonance which should imply that the ring has become anti aromatic and hence no resonance should be possible?

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    $\begingroup$ The Huckel's rule does not apply here. It is valid for monocyclic structures without any side groups. $\endgroup$ Apr 5 '16 at 11:33
  • $\begingroup$ I know that it is valid only for monocylic rings but I am not sure about the side group constrain because I have been given questions as practice where a carbon in a ring was attached to an oxygen by a double bond. $\endgroup$
    – Raksh23
    Apr 5 '16 at 11:39
  • $\begingroup$ chemistry.stackexchange.com/questions/22100/… $\endgroup$
    – Mithoron
    Apr 5 '16 at 11:49
  • $\begingroup$ @Mithoron In the phenoxide case,doesn't the compound become anti aromatic owing to 8 electrons and hence resonance shouldn't even be possible?(I am confused about counting electrons while judging it's aromaticity.Is it the number of electrons present in the ring in any resonating (in phenoxide case it will be 6 as in any structure 3 pairs of electrons are present in ring) or the number of electrons in conjugation (which becomes 8 in phenoxide case including 3 pairs of electrons in benzene and 1 pair of electrons from oxygen). $\endgroup$
    – Raksh23
    Apr 5 '16 at 12:15
  • $\begingroup$ No the electrons outside the ring are not counted $\endgroup$
    – orthocresol
    Apr 5 '16 at 14:37