Synthesis of Axially Chiral Cationic Benzo[ c ]phenanthridinium Derivatives.

Cationic polycyclic aromatic compounds containing one or more nitrogen atom(s), also known as azonia polycyclic aromatic compounds, form a valuable class of molecules because of their fluorescent and/or medicinal properties. N -Arylated hydroisoquinoline derivatives were synthesized through an aryne aza-Diels–Alder cycloaddition/ N -arylation sequence. A subsequent two-electron oxidation allowed the synthesis of some axially chiral cationic benzo[ c ]phenanthridinium derivatives. The structural and optical properties of some of these molecules were determined. Their chirality was evidenced experimentally by single-crystal X-ray diffraction and¹ H NMR spectroscopy, and their conformational behavior was examined by computational DFT methods. [ABSTRACT FROM AUTHOR]