Bowl-Shaped π-Extended Phosphangulenes: Synthesis and Structure-Dependent Modulation of Circularly Polarized Luminescence.

Bowl-shaped conjugated materials have emerged as a compelling class of materials due to their unique structural topology and exceptional chiral optoelectronic characteristics. Among these, phosphorus-embedded curved polycyclic aromatic phosphangulenes represent a particularly intriguing yet underexplored family, as their development has been hindered by synthetic challenges. We present an efficient synthetic strategy for two novel π-extended phosphangulene derivatives (P-PTz and P-DOPTz), establishing their first application in circularly polarized luminescence (CPL) systems. The chalcogen-dependent electronic modulation through sulfur oxidation enables remarkable emission color tuning across blue, green, and red spectral regions, with additional solvent-polarity-responsive characteristics. Notably, these compounds exhibit strong phosphorescence emission in cryogenic solution and thin-film states. This study not only validates the potential of bowl chirality in phosphangulenes as a design principle for CPL-active materials but also provides a foundation for developing advanced functional materials with multifarious optoelectronic applications.