Posts Tagged ‘o/p director of aromatic electrophilic substitution’

Aromatic electrophilic substitution. A different light on the bromination of benzene.

Wednesday, March 12th, 2014
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My previous post related to the aromatic electrophilic substitution of benzene using as electrophile phenyl diazonium chloride. Another prototypical reaction, and again one where benzene is too inactive for the reaction to occur easily, is the catalyst-free bromination of benzene to give bromobenzene and HBr. 

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The first curly arrows. The dénouement.

Monday, July 23rd, 2012
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Recollect, Robinson was trying to explain why the nitroso group appears to be an o/p director of aromatic electrophilic substitution. Using σ/π orthogonality, I suggested that the (first ever) curly arrows as he drew them could not be the complete story, and that a transition state analysis would be needed. Here it is. 

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