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Thionation-enhanced through-space electronic coupling and excited-state dynamics in helicene diimides
Analia D'Orazio-Colman1, Amalnadh T2, Sona Saji2
1Julius-Maximilians-Universität Würzburg, Institut für Organische Chemie, Am Hubland, D-97074 Würzburg, Germany.
None:
Thionation provides a simple heteroatom substitution strategy to enhance through-space electronic coupling in helically constrained π-systems. A thionated [8]helicene diimide shows pronounced LUMO stabilization and nearly doubled electronic coupling between the spatially aligned imide units. Spectroscopic and computational studies reveal enhanced charge delocalization and altered excited-state dynamics.
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