Pluripotent Features of Doubly Thiophene‐Fused Benzodiphospholes as Organic Functional Materials

Linear ladder‐type π‐conjugated molecules have attracted much interest because of their intriguing physicochemical properties. To modulate their electronic structures, an effective strategy is to incorporate main‐group elements into ladder‐type π‐conjugated molecules. In line with this strategy, a variety of ladder‐type π‐conjugated molecules with main‐group elements have been synthesized to explore their potential utility as organic functional materials. In this context, phosphole‐based π‐conjugated molecules are highly attractive, owing to their unique optical and electrochemical properties, which arise from the phosphorus atom. Herein, the synthesis and physicochemical properties of doubly thiophene‐fused benzodiphospholes, as a new class of phosphole‐based ladder‐type π‐conjugated molecule, are reported. Systematic investigations into the physicochemical properties of doubly thiophene‐fused benzodiphospholes revealed their pluripotent features: intense near‐infrared fluorescence, excellent two‐photon absorption property, and remarkably high electron‐transporting ability. This study demonstrates the potential utility of doubly thiophene‐fused benzodiphospholes as organic functional materials for biological imaging, nonlinear optics, organic transistors, and organic photovoltaics. Climb the ladder: The synthesis and physicochemical properties of doubly thiophene‐fused benzodiphospholes, as a new class of phosphole‐based, ladder‐type, π‐conjugated molecules, are reported. A systematic investigation into the physicochemical properties of doubly thiophene‐fused benzodiphospholes reveals their pluripotent features (see figure).