A diastereoselective Scholl reaction: point-to-helical chirality transfer in molecular nanographenes

Abstract

Stereoselective control of molecular nanographene helicity has been achieved by a point-to-helical chirality transfer during the Scholl graphitization reaction to obtain compound 4. Density functional theory calculations indicate that the complete diastereoselective process takes place mainly under kinetic control. Circular dichroism and circularly polarised luminescence studies of both enantiomers show the expected mirror images, with a dissymmetry factor (g_lum) value of 1.0 × 10⁻³ determined at 470 nm and a circularly polarized luminescence brightness (B_CPL) of 4.9 M⁻¹ cm⁻¹.