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Predict the major product in following reaction:

Nucleophilic substitution in 1,4‐dichlorobenzene

In my view this reaction will proceed via benzyne intermediate and $\ce{NH2-}$ will act as a base and substitute one of the chlorine. After benzyne formation as $\ce{Cl}$ is ortho/para directing my view was that $\ce{NH2-}$ will attach to the meta position.

However, the answer key says overwise. Any ideas?

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  • $\begingroup$ Think about which species can act as electrophiles in EAS, would ammonia work? $\endgroup$ – AS_1000 Oct 30 '17 at 10:58
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    $\begingroup$ @AS_1000 in my view $\ce{NH_2 ^{-}}$ acts as a nucleophile $\endgroup$ – user471651 Oct 30 '17 at 11:25
  • $\begingroup$ Look up Meisenheimer intermediates rather than Wheland intermediates. The former are valid for nucleophilic aromatic substitutions. $\endgroup$ – Beerhunter Oct 30 '17 at 21:53
  • $\begingroup$ Note that halides are weak EWG's. So, para product is preferred $\endgroup$ – Rahul Verma Aug 4 '19 at 14:32

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