Aromatic Ring-Fused Carborane-Based Luminescent π-Conjugated Polymers.

A series of π-conjugated polymers linked by benzocarborane (1,2-(buta-1',3'-diene-1',4'-diyl)-1,2-dicarbadodecaborane) were synthesized via Sonogashira-Hagihara polycondensation reaction. The opened molecular structure of diiodo monomer containing benzocarborane resulted in fast polymerization and high molecular weights. The obtained polymers were fully characterized by (1) H, (13) C, and (11) B NMR spectroscopies. UV-vis absorption and photoluminescence studies revealed the acceptor-profile of benzocarborane. Unlike the polymers linked by o-carborane, these polymers exhibited strong luminescence in the solution state, presumably because the inductive effect of carborane is dominant, rather than cage-π interactions.