The intrinsic π–π* fluorescence of acridine is weak due to the deactivation via coupling with a close-lying non-emissive 1n–π* state. By employing the lone pair of acridine to establish coordination bonds in a series of two-coordinate Cu(I) and Ag(I) complexes, significantly enhanced intrinsic fluorescence of acridinyl is observed with a photoluminescent quantum yield (ΦPL) approaching 50%. Using chiral camphorsulfonate counterions, the cationic complex was induced to emit circularly polarized fluorescence with a reasonable glum of 5 × 10−3.
