Organic Chemistry Practice Problems and Problem Sets
SNAr
Draw in the arrows to show the electron flow and resonance forms in the nucleophilic aromatic substitution reaction below.
Note: Depending on the textbook, nucleophilic aromatic substitution is referred to as NAS, SNAr, or addition-elimination.
SNAr is sort of like SN2, except the leaving group doesn't leave right away; a tetrahedral intermediate is formed first.
The trick with SNAr (or NAS, addition-elimination, etc.) is to draw resonance forms that stabilizes the negative charge that forms. That's why EWG increase the rate of SNAr (they stabilize negative charges).
MendelSet practice problem # 611 submitted by Matt on July 10, 2011.