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I am in a project in organic synthesis writing about nucleophilic aromatic substitustion reactions. I cant´t figure out why the nucleophile (benzylmethylamine) attacks the chloro-binded carbon when bromide is a better leaving groupe?enter image description here (See picture)

Waylander
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Tore-Andre Johan Øverby
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    A halogen in the 2 (and 4) position to N is activated towards nucleophilic attack because of the polarity of the C-N bond and the capacity of the heterocycle to stabilise -ve charge as you have drawn. There is no such polarity with the C-S bond and it cannot stabilise -ve charge – Waylander Apr 25 '20 at 16:21
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    That's the main reason, but also "Br is a better leaving group" isn't true: for SNAr reactions it's F > Cl > Br > I, the reasons are covered in all organic chemistry texts and (for example) here: https://chemistry.stackexchange.com/questions/5690/why-are-fluorides-more-reactive-in-nucleophilic-aromatic-substitutions-than-brom?rq=1 – orthocresol Apr 25 '20 at 16:41

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