Chemical resolution of spiroindanones and synthesis of chiroptical polymers with circularly polarized luminescence

Abstract

Herein, the synthesis and chemical resolution of 1,1′-spirobisindane-3,3′-dione have been accomplished utilizing inexpensive and readily available benzaldehyde and acetone as starting materials, and (1R,2R)- or (1S,2S)-1,2-diphenylethane-1,2-diol as a recyclable chiral resolution reagent. The further transformation of R- and S-1,1′-spirobisindane-3,3′-dione into chiral monomers and polymers has been achieved by the reasonable design of the synthetic route and the optimization of the polymerization conditions. The resulting chiroptical polymers exhibit blue emission with thermally activated delayed fluorescence (TADF), excellent optical activities with circular dichroism intensities per molar absorption coefficient (g_abs) of up to 6.4 × 10⁻³, and intense circularly polarized luminescence (CPL) with luminescence dissymmetry factor (g_lum) values of up to 2.4 × 10⁻³.