Blue Emission of a Soluble Poly(p-phenylene) with a Cross-Conjugated Bisimidazole-Based Chromophore

✍ Scribed by Frank Dierschke; Klaus Müllen

• Book ID: 102490029
• Publisher: John Wiley and Sons
• Year: 2007
• Tongue: English
• Weight: 180 KB
• Volume: 208
• Category: Article
• ISSN: 1022-1352
• DOI: 10.1002/macp.200600412

✦ Synopsis

Abstract

A novel poly(p‐phenylene) (6) has been synthesized by a cruciform combination of a polyphenylene backbone with 2,2′‐(p‐phenylene)‐bis(4,5‐diphenylimidazole) (5) as an additional, orthogonal chromophore. Polymer 6 showed in solution and in the solid state, a blue‐green emission, which is obviously arising from the second bisimidazole‐based chromophore. UV‐Vis spectroscopy, and cyclic voltammetry revealed that the optical and electronic properties of 6 were fully determined by the incorporated 2,2′‐(1,4‐phenylene)bisimidazole structure. The bisimidazole unit led to high solubility and, despite the steric demand of the substituents, at the same time to the blue‐green emission of the poly(p‐phenylene) (6). In addition, the oxidation of 6 with potassium ferricyanide yielded a low bandgap polymer with a quinoid‐type structure and a bandgap of 1.6 eV.

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