Synthesis, Electronic Properties and OLED Devices of Chromophores Based on λ5‐Phosphinines

We have synthesized a new series of 2,4,6-triaryl-$\lambda ^5$-phosphinines containing different substituents both at the carbon-backbone and the phosphorus atom of the six-membered heterocycle. Their optical and redox properties were studied in detail, supported by in-depth theoretical calculations. The modularity of the synthetic strategy allowed us to establish structure-property relationships for this class of compounds and an OLED based on a blue phosphinine emitter could be developed for the first time.