Copper-Catalyzed Desymmetrization toward Planar Chiral Disubstituted [2.2]Paracyclophanes: A Route to Solid-State CPL Materials

Abstract Enantiomerically enriched [2.2]paracyclophanes (PCPs), particularly those bearing two functional groups on distinct decks, constitute privileged scaffolds for circularly polarized luminescence (CPL) materials owing to their inherent stable planar chirality and unique optoelectronic properties. Nevertheless, the efficient and enantioselective construction of structurally diverse PCPs equipped with synthetically versatile handles suitable for solid-state applications persists as a formidable challenge. Herein, we disclose a modular asymmetric copper-catalyzed azide–alkyne cycloaddition (CuAAC) desymmetrization of prochiral dialkynyl PCPs. This methodology enables the concise assembly of a diverse array of highly functionalized disubstituted PCPs in high yields with excellent enantioselectivities (up to 93% yield and >99% ee) while incorporating optically active terminal alkyne and triazole moieties ideally poised for downstream diversification. Subsequent elaborations of these chiral mono-terminal alkyne substituted PCPs furnish complex difunctionalized derivatives with complete retention of enantiopurity. As a proof-of-concept application, a pyrene-functionalized PCP derivative 5a displays pronounced solid-state CPL activity, delivering an impressive dissymmetry factor (glum = −2.7 × 10–3) alongside a high fluorescence quantum yield (ΦF = 0.59). This strategy establishes a modular platform for accessing enantiopure disubstituted PCPs, furnishing promising candidates for advanced solid-state chiral emitters in photonic technologies.