Synthesis, structure and optoelectronic properties of rigid 3D tetraindeno-fused spirofluorene with thioxanthene or dioxothioxanthene substitutes

Tetraindeno-fused spirofluorene based blue emitters with thioxanthene (Spiro-4S) or dioxothioxanthene (Spiro-4SO2) substitutes have been synthesized and characterized. Their thermal, photophysical, and electrochemical properties have also been studied. The appealing feature of this study is their 3D geometries with cruciform conjugated backbones, whose interactions are clearly revealed by single crystal analysis. Notably, this conformation is beneficial for reducing the trend of aggregation quenching and it is highly expected that these two molecules will have isotropic charge-transport and optical properties.