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Published on: August 22, 2018
How Do Face-to-Face Stacked Aromatic Rings Activate Each Other to Electrophilic Aromatic Substitution?
Muhammad Kazim1, Muyuan Wang1, Srini Vemulapalli2
1Department of Chemistry, Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218, United States.
Abstract:
We have found that face-to-face π-stacked aromatic rings show the propensity to activate one another toward electrophilic aromatic substitution through direct influence of the probe aromatic ring by the adjacent stacked ring, rather than through the formation of relay or "sandwich complexes." This activation remains in force even when one of the rings is deactivated through nitration. The resulting dinitrated products are shown to crystallize in an extended parallel offset stacked form, in stark contrast to the substrate.
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