| Abstract
| - We present a new synthetic approach to both phenylquinoxaline polymers and low molarmass glasses. A palladium-catalyzed coupling of arylalkynes and bromobenzenes and subsequent oxidationof the triple bonds lead to the corresponding benziles. Reaction with diaminobenzidine yields poly(phenylquinoxalines) (PPQs), whereas the reaction with 1,2-diaminobenzenes leads to low molar massbis(phenylquinoxalines) (BPQs) and tris(phenylquinoxalines) (TPQs). Both PPQs and TPQs carry tert-butyl or CF3− substituents and are fully soluble in chlorinated hydrocarbons. The starburst TPQs areable to form stable, low molar mass glasses. Cyclic voltammetry reveals that the TPQs have low-lyinglowest unoccupied molecular orbitals levels at about −3.6 eV and are attractive as electron-transportmaterials in organic light-emitting diodes (LEDs). Two-layer LEDs with poly(phenylenevinylene) werefabricated that show a maximum brightness of 450 cd/m2.
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