Spiro‑Linked Double Tetraphenylethenes: Solid-State Emission and Circularly Polarized Luminescence Imaging

Herein, we report the synthesis and structural characterization of two spiro-linked tetraphenylethenes and investigate their optical properties in solution, as aggregates, and in the solid state. This family comprises two double spirobisanthracene-tetraphenylethene hybrid systems. Approaching the synthesis and understanding the structure of these unexplored spiro-systems opens the door to studying their properties both in solution and in the solid state. Besides the structural novelty of the prepared compounds, their solid-state optical properties are remarkable. White and blue emissions are observed in the double spirobisanthracene-tetraphenylethene hybrid derivatives. In addition, one of the synthesized compounds is chiral, and separation of its enantiomers enable the study of their chiroptical properties, revealing circularly polarized luminescence in films, aggregates and dispersions. Crystals were analyzed via circularly polarized luminescence microscopy, allowing the identification of racemic and enantiopure crystals via single-particle analysis. This work paves the way for a further extension of the spirobisanthracene capabilities toward their implementation in emissive devices.